Sample: Electromagnetic Waves Dataset: USNA Physics Spring 2007 Anon Student Id Session Id Time Time Zone Student Response Type Student Response Subtype Tutor Response Type Tutor Response Subtype Level(Module) Level(Group) Problem Name Step Name Attempt At Step Outcome Selection Action Input Feedback Text Feedback Classification Help Level Total # Hints KC(Default) KC Category(Default) School Class CF(score) CF(parse) DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:44:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:44:25.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:44:43.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/M" Undefined variable: M 1 DEFINE-AMPLITUDE USNA SP212 General Physics II 2 DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:44:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:45:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 66 (= (/ ampE_WAVE ampM_WAVE) c) DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:45:18.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-44-02 2007-04-06 20:45:22.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 98 DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:45:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:46:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:46:46.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=231 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:46:53.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:47:00.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:47:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:48:40.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 INCORRECT 1 "P=I/c" Units are inconsistent. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 24 (= power_TRANSMITTER_1 (/ int_P_TRANSMITTER_1 c)) DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:48:47.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 Units are inconsistent. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 19 DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:52:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:53:01.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:55:01.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:55:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-45-37 2007-04-06 20:55:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 94 DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 6 DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:40.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-2 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-2 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 14 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 0 "s=2*s1" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 20 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 0 "s=2*s1" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 20 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:58:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s=2*s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II 20 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-3 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 21 DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 1 "c=s/t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 65 (= c (/ dist_PULSE_13 t_13)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "c=s/t" WRITE-SDD USNA SP212 General Physics II 65 (= c (/ dist_PULSE_13 t_13)) DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "s1" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 2 "t" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-19-57-13 2007-04-06 20:59:56.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 96 DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:19.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:37.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 2 DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:52.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DEFINE-POWER-VAR USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 2 DEFINE-POWER-VAR USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:01:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:02:09.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:02:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 3 DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:02:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:03:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:03:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P1";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 22 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:04:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 0 "P1*.28=P" GIVEN-FRACTION USNA SP212 General Physics II (= (* power_ELECTRIC_OUTPUT_COLLECTOR_1 0.28) power_COLLECTOR_SUNLIGHT_1) DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:04:36.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 What equation do you wish to write? 1 GIVEN-FRACTION USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:04:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 0 "P1=P*.28" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* power_COLLECTOR_SUNLIGHT_1 0.28)) DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:22:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 23 DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:23:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 "P/A=I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 66 (= (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR) int_COLLECTOR_SUNLIGHT_1) DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:23:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-00-22 2007-04-06 21:23:09.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 98 DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:23:45.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DEFINE-INTENSITY USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:24:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:34:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-3 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 12 DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:34:53.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 32 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:34:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:35:01.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 49 DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:35:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:22.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Thrust;time=T0;dir=NIL;mag=105 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 48 DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:24.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F There is indeed a force on the sail due to the sunlight, but it is not a thrust force. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:32.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Applied;time=T0;dir=NIL;mag=105 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:34.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F There is indeed a force on the sail due to the sunlight, but it is not a applied force. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:43.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=105 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 2 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 68 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:36:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 INCORRECT 3 "A" Unable to solve for A. One thing you probably need is an equation specifying the given value of F. 1 1 USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:37:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 3 "F= 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 76 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:37:07.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DB8B7 DB8B7-Apr06-20-23-36 2007-04-06 21:37:15.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 87 DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:26:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:26:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:26:52.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 INCORRECT Answer-1 "120 V/m" Units are inconsistent. 1 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:26:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:27:03.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:27:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT speed-equals-wave-speed No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:02.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 8 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-25-57 2007-03-26 23:28:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 92 DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:29:21.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-1 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=247 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 6 DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:29:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:29:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:30:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:30:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:30:21.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:30:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:30:37.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:12.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT uniform-intensity-to-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 20 DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:26.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-5 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:31.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:31:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 15 DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:32:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 59 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:32:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-28-47 2007-03-26 23:32:17.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 90 DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:33:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="2MW" DEFINE-AREA USNA SP212 General Physics II 12 DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 14 DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 9 DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:36.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:34:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 4 DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 14 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:13.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:24.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Good! You should be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-5 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:35:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "Ps=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 58 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P=Ps" GIVEN-FRACTION USNA SP212 General Physics II 57 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 power_COLLECTOR_SUNLIGHT_1) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 1 "P=-Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (- power_COLLECTOR_SUNLIGHT_1)) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 INCORRECT 1 "P*.28=Ps" GIVEN-FRACTION USNA SP212 General Physics II 56 (= (* power_ELECTRIC_OUTPUT_COLLECTOR_1 0.28) power_COLLECTOR_SUNLIGHT_1) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:25.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 3 "A" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-32-38 2007-03-26 23:36:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476189 m^2" USNA SP212 General Physics II 88 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:37:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:38:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:38:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:38:48.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 12 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:05.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=47 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 13 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 21 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 16 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:46.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-6 label="sa";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 28 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:39:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:25.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT grav-energy No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:26.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT spherical-intensity-to-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 23 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:40:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 42 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 59 DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 CORRECT 2 "P = 8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 CORRECT 2 "P = 8.672666475151953e-6 Pa" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:40.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 INCORRECT 3 "F=P/A" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II 58 (= Fp_SAIL_SUNLIGHT_1 (/ Pr_SAIL A_SAIL)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:47.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 INCORRECT 3 "F=A/P" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (/ A_SAIL Pr_SAIL)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 3 "F=A*P" PRESSURE-FORCE USNA SP212 General Physics II 78 (= Fp_SAIL_SUNLIGHT_1 (* A_SAIL Pr_SAIL)) DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:41:59.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DC6E9 DC6E9-Mar26-22-37-05 2007-03-26 23:42:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.0958307692313 m^2" USNA SP212 General Physics II 89 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:08:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8.0 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:14.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-2 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 8 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:29.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 5 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 9 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 4 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:49.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=221 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r= 8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:09:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:10:12.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:10:51.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:10:52.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT beat-frequency No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:10:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT You should be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:10:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 9 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 4 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:15.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -1 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:30.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-7 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -6 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:11:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 38 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:12:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:12:12.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 69 DC6EF DC6EF-Apr22-20-06-06 2007-04-22 21:13:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 64 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:18:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Answer-1 "583.333 m^2" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:18:45.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Answer-1 label=583.333 m^2 583.333 m^2 is not the correct value for the area of the collector. When you have entered enough equations, ask Andes to solve for the area of the collector, then transfer the result to this answer box. 1 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:18:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:18:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -10 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:18:58.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -9 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 1 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:19:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II -4 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:20:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 5 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:20:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:20:18.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:20:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Yep. You should be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:20:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT You should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II -5 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -10 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 34 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 29 DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:21:47.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-13-39 2007-04-22 21:22:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476 m^2" USNA SP212 General Physics II 57 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:25:46.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Answer-2 "1.5384e4 m^2" DEFINE-INTENSITY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:45.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-2 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:26:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 15 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:30.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-3 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=99 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 10 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 18 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:27:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:34.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:35.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT net-intensity No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT A good step would be introducing a variable for the pressure at the sail at T0. 5 DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 HINT Define a variable for the pressure at the sail at T0 by using the Add Variable command on the Variable menu and selecting Pressure. 6 6 DEFINE-PRESSURE USNA SP212 General Physics II 13 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 8 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:28:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 28 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:03.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:10.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 42 DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:33.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 INCORRECT 3 "I=P/A" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II 41 (= int_SAIL_SUNLIGHT_1 (/ Pr_SAIL A_SAIL)) DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:29:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:30:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 60 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:30:04.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-23-06 2007-04-22 21:30:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 72 DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT Answer-1 "1.28 s" DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:56.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:33:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:04.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 USNA SP212 General Physics II DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -9 DC6EF DC6EF-Apr22-20-32-34 2007-04-22 21:34:32.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.56 s" USNA SP212 General Physics II 19 DC791 DC791-May07-23-22-24 2007-05-08 00:22:40.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.00e-7 T" USNA SP212 General Physics II 31 DC791 DC791-May07-23-22-54 2007-05-08 00:23:09.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.56 s" USNA SP212 General Physics II 31 DC791 DC791-May07-23-23-26 2007-05-08 00:23:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.48e-4 W/m^2" USNA SP212 General Physics II 31 DC791 DC791-May07-23-23-56 2007-05-08 00:24:07.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440 m^2" USNA SP212 General Physics II 31 DC8F3 DC8F3-Apr29-14-56-50 2007-04-29 15:57:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DC8F3 DC8F3-Apr29-14-56-50 2007-04-29 15:57:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-56-50 2007-04-29 15:57:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= ampE_WAVE (* ampM_WAVE c)) DC8F3 DC8F3-Apr29-14-56-50 2007-04-29 15:57:21.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-56-50 2007-04-29 15:57:24.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:58:16.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-1 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 6 DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:58:22.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 CORRECT System-2 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:58:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:58:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=transmitter;agent=P;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 14 DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:18.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 15 DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-6 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=94 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 24 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 68 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:50.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 15:59:54.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 INCORRECT Answer-1 "P = 280000 W" Answers can be expressed as a simple equation with the name of the variable for the quantity that the problem asks you to find on the left hand side of equation. 1 USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 16:00:00.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 3 "I" USNA SP212 General Physics II DC8F3 DC8F3-Apr29-14-57-56 2007-04-29 16:00:04.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 2 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 96 DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:01:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:01:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:04:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:04:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-2 label="T";quant=period;subtype=NIL;body=sunlight;agent=NIL;time=NIL;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:06:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 21 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:06:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 22 DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:09:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:09:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 66 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:10:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II 67 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:10:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 CORRECT 2 "P = 2000000 W" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2000000 W)) DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:10:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 3 "A" USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-00-38 2007-04-29 16:10:13.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476189 m^2" USNA SP212 General Physics II 98 DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:14:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:18:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:18:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:01.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=123 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:12.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 CORRECT System-5 label="i";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 25 DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 33 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 53 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 CORRECT 2 "P = 8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 2 "P = 8.672666475151953e-6 Pa" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:38.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 72 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 4 "A" USNA SP212 General Physics II DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.0958307692313 m^2" USNA SP212 General Physics II 89 DC8F3 DC8F3-Apr29-15-11-39 2007-04-29 16:19:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" USNA SP212 General Physics II 100 DC96B DC96B-May01-09-41-24 2007-05-01 10:41:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 INCORRECT 0 "E=c*B" Undefined variables: (E B) 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:41:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 2 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:41:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 3 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:41:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 4 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:41:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 5 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 4 4 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DC96B DC96B-May01-09-41-24 2007-05-01 10:42:20.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:42:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 16 (= ampE_WAVE (DNUM 120 V/m)) DC96B DC96B-May01-09-41-24 2007-05-01 10:42:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-3 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 17 DC96B DC96B-May01-09-41-24 2007-05-01 10:42:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 61 (= ampE_WAVE (* c ampM_WAVE)) DC96B DC96B-May01-09-41-24 2007-05-01 10:42:54.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DC96B DC96B-May01-09-41-24 2007-05-01 10:42:59.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 " 4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DC96B DC96B-May01-09-43-28 2007-05-01 10:43:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:43:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DC96B DC96B-May01-09-43-28 2007-05-01 10:43:48.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DC96B DC96B-May01-09-43-28 2007-05-01 10:44:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -4 DC96B DC96B-May01-09-43-28 2007-05-01 10:44:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 5 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 6 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC96B DC96B-May01-09-43-28 2007-05-01 10:44:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:44:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 1 DC96B DC96B-May01-09-43-28 2007-05-01 10:45:05.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=158 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:45:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:45:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:45:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:45:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -4 DC96B DC96B-May01-09-43-28 2007-05-01 10:45:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 5 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC96B DC96B-May01-09-43-28 2007-05-01 10:45:51.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT 1 "P=4*$p*(r^2)*I" Undefined variable: I 1 DEFINE-INTENSITY USNA SP212 General Physics II 4 DC96B DC96B-May01-09-43-28 2007-05-01 10:46:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:11.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT #.(wb-quant '(define-variable "m" |NIL| |mass| |transmitter| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:12.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT #.(wb-quant '(define-variable "$w" |NIL| |angular-frequency| |transmitter| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:16.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT #.(wb-quant '(define-variable "$b" |NIL| |db-intensity| |transmitter| |T0| |all sources| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the intensity supplied to P at T0 due to the transmitter. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:17.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:21.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 8 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:22.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 9 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 7 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 10 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 11 HINT You should be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 12 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 3 3 DEFINE-INTENSITY USNA SP212 General Physics II -1 DC96B DC96B-May01-09-43-28 2007-05-01 10:46:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 13 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:46:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 43 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DC96B DC96B-May01-09-43-28 2007-05-01 10:47:23.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DC96B DC96B-May01-09-43-28 2007-05-01 10:47:28.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 74 DC96B DC96B-May01-09-47-58 2007-05-01 10:48:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DC96B DC96B-May01-09-47-58 2007-05-01 10:48:16.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DC96B DC96B-May01-09-47-58 2007-05-01 10:48:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -4 DC96B DC96B-May01-09-47-58 2007-05-01 10:48:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 6 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC96B DC96B-May01-09-47-58 2007-05-01 10:48:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:48:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 1 DC96B DC96B-May01-09-47-58 2007-05-01 10:49:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0MW" DEFINE-POWER-VAR USNA SP212 General Physics II 10 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DC96B DC96B-May01-09-47-58 2007-05-01 10:49:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AREA USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:49:21.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 INCORRECT 0 "P1=I*A" Undefined variables: (P1 A) 1 DEFINE-AREA USNA SP212 General Physics II 8 DC96B DC96B-May01-09-47-58 2007-05-01 10:49:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 DEFINE-AREA USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:49:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 9 DC96B DC96B-May01-09-47-58 2007-05-01 10:49:45.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT 0 "P1=I*A" Undefined variable: P1 1 DEFINE-POWER-VAR USNA SP212 General Physics II 8 DC96B DC96B-May01-09-47-58 2007-05-01 10:49:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT 0 "P=I*A" DEFINE-POWER-VAR USNA SP212 General Physics II 7 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC96B DC96B-May01-09-47-58 2007-05-01 10:49:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT 0 "P=I*A" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC96B DC96B-May01-09-47-58 2007-05-01 10:50:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:08.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT #.(wb-quant '(define-variable "$m" |NIL| |mass-per-length| |collector| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:11.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT #.(wb-quant '(define-variable "P" |NIL| |power| |electric_output| |T0| |all forces| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:13.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the area of the collector. 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:15.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:17.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:18.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 10 HINT energy-decay No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 7 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 11 HINT You should be introducing a variable for the power supplied to the collector from the sunlight at T0. 8 DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:50:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 12 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 9 9 DEFINE-POWER-VAR USNA SP212 General Physics II 2 DC96B DC96B-May01-09-47-58 2007-05-01 10:51:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 13 CORRECT Var-7 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:51:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P1=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 46 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC96B DC96B-May01-09-47-58 2007-05-01 10:51:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 ".28*P1=P" GIVEN-FRACTION USNA SP212 General Physics II (= (* 0.28 power_COLLECTOR_SUNLIGHT_1) power_ELECTRIC_OUTPUT_COLLECTOR_1) DC96B DC96B-May01-09-47-58 2007-05-01 10:51:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DC96B DC96B-May01-09-47-58 2007-05-01 10:51:28.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 " 7440.476190476189 m^2" USNA SP212 General Physics II 78 DC96B DC96B-May01-09-51-59 2007-05-01 10:52:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DC96B DC96B-May01-09-51-59 2007-05-01 10:52:11.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-1 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DC96B DC96B-May01-09-51-59 2007-05-01 10:52:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 3 HINT Try introducing a variable for the intensity supplied to the sail at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 4 HINT Define a variable for the intensity supplied to the sail at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II 7 DC96B DC96B-May01-09-51-59 2007-05-01 10:52:33.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DC96B DC96B-May01-09-51-59 2007-05-01 10:52:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 13 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DC96B DC96B-May01-09-51-59 2007-05-01 10:52:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:52:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 8 DC96B DC96B-May01-09-51-59 2007-05-01 10:53:27.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-3 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=110 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 9 DC96B DC96B-May01-09-51-59 2007-05-01 10:53:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:53:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:53:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:53:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DC96B DC96B-May01-09-51-59 2007-05-01 10:53:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 12 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DC96B DC96B-May01-09-51-59 2007-05-01 10:53:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 INCORRECT 1 "P=2*I/c" Undefined variable: P 1 DEFINE-PRESSURE USNA SP212 General Physics II 11 DC96B DC96B-May01-09-51-59 2007-05-01 10:54:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:26.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT #.(wb-quant '(define-variable "P" |NIL| |power| |sail| |T0| |all forces| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:28.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT #.(wb-quant '(define-variable "h" |NIL| |height| |sail| |T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT #.(wb-quant '(define-variable "n" |NIL| |index-of-refraction| |sail| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the pressure at the sail at T0. 4 4 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:31.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 HINT "OK" What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 5 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:34.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:34.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 8 HINT beat-frequency No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 7 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 9 HINT Try introducing a variable for the pressure at the sail at T0. 8 DEFINE-PRESSURE USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 10 HINT Define a variable for the pressure at the sail at T0 by using the Add Variable command on the Variable menu and selecting Pressure. 9 9 DEFINE-PRESSURE USNA SP212 General Physics II 6 DC96B DC96B-May01-09-51-59 2007-05-01 10:54:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 11 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 7 DC96B DC96B-May01-09-51-59 2007-05-01 10:54:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 1 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 26 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 5 CORRECT 2 "P * (299792458 m/s) = 2600 kg/s^3" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 27 (= (* Pr_SAIL (DNUM 299792458 m/s)) (DNUM 2600 kg/s^3)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 2 "P * (299792458 m/s) = 2600 kg/s^3" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 27 (= (* Pr_SAIL (DNUM 299792458 m/s)) (DNUM 2600 kg/s^3)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 6 CORRECT 3 "P = 8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 CORRECT 3 "P = 8.672666475151953e-6 Pa" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Pr_SAIL (DNUM 8.672666475151952e-6 Pa)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:47.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 INCORRECT 4 "P=F/A" Undefined variable: A 1 DEFINE-AREA USNA SP212 General Physics II 26 DC96B DC96B-May01-09-51-59 2007-05-01 10:54:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:54:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 4 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 46 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DC96B DC96B-May01-09-51-59 2007-05-01 10:54:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 5 "A" USNA SP212 General Physics II DC96B DC96B-May01-09-51-59 2007-05-01 10:55:07.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 63 DC96B DC96B-May01-09-51-59 2007-05-01 10:55:15.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 74 DC96B DC96B-May01-09-55-41 2007-05-01 10:55:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:55:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DC96B DC96B-May01-09-55-41 2007-05-01 10:56:00.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DC96B DC96B-May01-09-55-41 2007-05-01 10:56:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DC96B DC96B-May01-09-55-41 2007-05-01 10:56:08.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -9 DC96B DC96B-May01-09-55-41 2007-05-01 10:56:29.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -11 DC96B DC96B-May01-09-55-41 2007-05-01 10:56:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -1 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DC96B DC96B-May01-09-55-41 2007-05-01 10:56:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:56:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -6 DC96B DC96B-May01-09-55-41 2007-05-01 10:57:04.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DC96B DC96B-May01-09-55-41 2007-05-01 10:57:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 3 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DC96B DC96B-May01-09-55-41 2007-05-01 10:57:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:49.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "$m" |NIL| |mass-per-length| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:51.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "$w" |NIL| |angular-frequency| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT #.(wb-quant '(define-variable "f" |NIL| |frequency| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the duration of the interval from T0 to T2. 4 4 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:53.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:56.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT doppler-frequency No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 7 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 8 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 9 HINT Try introducing a variable for the speed of the pulse. 9 DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:57:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 10 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 10 10 DEFINE-SPEED USNA SP212 General Physics II -2 DC96B DC96B-May01-09-55-41 2007-05-01 10:58:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 11 CORRECT Var-7 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT You should be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -7 DC96B DC96B-May01-09-55-41 2007-05-01 10:58:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-8 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT You should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II -12 DC96B DC96B-May01-09-55-41 2007-05-01 10:58:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-9 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II -11 DC96B DC96B-May01-09-55-41 2007-05-01 10:58:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 10:58:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 HINT Because v is the speed of the pulse from T0 to T2, and s2 is the distance travelled, and t is the duration of the trip, write v=s2/t. 6 6 WRITE-SDD USNA SP212 General Physics II -16 DC96B DC96B-May01-09-55-41 2007-05-01 10:59:08.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 7 INCORRECT 0 "s=v*ta" Undefined variable: ta 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II -17 DC96B DC96B-May01-09-55-41 2007-05-01 10:59:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 8 CORRECT 4 "s2=s1+s" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_23 dist_PULSE_12)) DC96B DC96B-May01-09-55-41 2007-05-01 10:59:39.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 INCORRECT 3 "vc=c" Undefined variable: vc 1 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 HINT Because v is the speed of the pulse from T0 to T2, and s2 is the distance travelled, and t is the duration of the trip, write v=s2/t. 6 6 WRITE-SDD USNA SP212 General Physics II -22 DC96B DC96B-May01-09-55-41 2007-05-01 11:00:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 8 CORRECT 5 "v=s2/t" WRITE-SDD USNA SP212 General Physics II 22 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DC96B DC96B-May01-09-55-41 2007-05-01 11:00:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 17 DC96B DC96B-May01-09-55-41 2007-05-01 11:00:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 3 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DC96B DC96B-May01-09-55-41 2007-05-01 11:00:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 12 DC96B DC96B-May01-09-55-41 2007-05-01 11:00:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 INCORRECT 2 "s2=vc*t" Undefined variable: vc 1 USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 CORRECT 0 "t" USNA SP212 General Physics II DC96B DC96B-May01-09-55-41 2007-05-01 11:00:54.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 42 DC995 DC995-Apr04-21-51-51 2007-04-04 22:52:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DC995 DC995-Apr04-21-51-51 2007-04-04 22:52:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:53:06.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:53:10.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:57:02.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT electromagnetic-wave-field-amplitude Right indeed. A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:57:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:57:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= ampE_WAVE (* ampM_WAVE c)) DC995 DC995-Apr04-21-51-51 2007-04-04 22:57:26.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DC995 DC995-Apr04-21-51-51 2007-04-04 22:57:32.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DC995 DC995-Apr04-21-57-57 2007-04-04 22:58:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC995 DC995-Apr04-21-57-57 2007-04-04 22:58:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 11 DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:10.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 22:59:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 8 DC995 DC995-Apr04-21-57-57 2007-04-04 23:01:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 6 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 7 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 8 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 2 DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:40.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 9 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=94 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 3 DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -2 DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 INCORRECT 0 "r=.8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -3 (= r_P_TRANSMITTER_1 (DNUM 0.8 km)) DC995 DC995-Apr04-21-57-57 2007-04-04 23:02:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 6 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 7 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC995 DC995-Apr04-21-57-57 2007-04-04 23:03:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:03:18.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |all sources| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:03:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:04:53.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT (charge-force-efield ((?axis . y))) No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:04:59.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT net-potential No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 5 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 6 DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 7 7 DEFINE-INTENSITY USNA SP212 General Physics II 2 DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 8 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 3 DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:05:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -2 DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:13.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-6 label="ho";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -7 DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:32.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-7 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -12 DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 32 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DC995 DC995-Apr04-21-57-57 2007-04-04 23:06:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DC995 DC995-Apr04-21-57-57 2007-04-04 23:07:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 63 DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=all forces;time=T0;value="" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:24.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT Click on the light bulb button or 'explain further' for suggestions on how to solve this problem. 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 3 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 4 4 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:32.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 6 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -7 DC995 DC995-Apr04-22-07-26 2007-04-04 23:08:57.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -8 DC995 DC995-Apr04-22-07-26 2007-04-04 23:09:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 2 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC995 DC995-Apr04-22-07-26 2007-04-04 23:09:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:09:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:09:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II -3 DC995 DC995-Apr04-22-07-26 2007-04-04 23:10:24.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:10:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 7 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DC995 DC995-Apr04-22-07-26 2007-04-04 23:11:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:11:58.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT magnetic-flux-constant-field No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:06.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT (net-field-magnetic ((?axis . x))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 2 DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Your goal should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:14:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II -3 DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II -2 DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -7 DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:12.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 37 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 32 DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 27 DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "P" USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:36.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 INCORRECT Answer-1 " 2000000 W" Units are inconsistent. 1 1 USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 3 CORRECT 3 "A" USNA SP212 General Physics II DC995 DC995-Apr04-22-07-26 2007-04-04 23:15:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 2 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 55 DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:32.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="l";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:41.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:27:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -4 DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:05.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -6 DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 4 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -1 DC995 DC995-Apr04-22-25-39 2007-04-04 23:28:30.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -2 DC995 DC995-Apr04-22-25-39 2007-04-04 23:29:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 8 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DC995 DC995-Apr04-22-25-39 2007-04-04 23:29:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:29:50.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "v" |instantaneous| |speed| |pulse| |T2| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:29:57.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "T" |NIL| |period| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:30:02.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Yep. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 4 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:29.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 5 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:32.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT harmonic-of No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 6 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 7 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 HINT You should be introducing a variable for the speed of the pulse. 8 DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 9 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 9 9 DEFINE-SPEED USNA SP212 General Physics II 3 DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:51.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 10 CORRECT Var-5 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT A good step would be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:32:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -2 DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-6 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Try introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II -7 DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II -6 DC995 DC995-Apr04-22-25-39 2007-04-04 23:33:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:34:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:34:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:34:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:34:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:34:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and s2 is the distance travelled, and t is the duration of the trip, write v=s2/t. 6 6 WRITE-SDD USNA SP212 General Physics II -11 DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 0 "v=s2/t" WRITE-SDD USNA SP212 General Physics II 33 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 28 DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 4 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 23 DC995 DC995-Apr04-22-25-39 2007-04-04 23:38:46.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 2 1 INCORRECT 2 "T02-VAR=s+s1" Undefined variables: (T02 VAR) 1 USNA SP212 General Physics II 22 DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:00.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 2 2 INCORRECT 2 "?T02-VAR=s+s1" Syntax error in T02-VAR=s+s1 1 USNA SP212 General Physics II ? DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 5 HINT Why don't you continue working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 6 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 7 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 8 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:43.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 2 3 INCORRECT 2 "?T02-VAR=s+s1" Syntax error in T02-VAR=s+s1 1 USNA SP212 General Physics II 21 ? DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 Unknown 9 HINT The equation or the units in it are not in a recognizable form. 2 USNA SP212 General Physics II DC995 DC995-Apr04-22-25-39 2007-04-04 23:39:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 Unknown 10 HINT Though I can't tell exactly what the mistake is, a few common sources of errors are: (a) Unit symbols are case sensitive. (b) Multiplication always requires an explicit multiplication sign: W=m*g, NOT W=mg. (c) Units attach only to numbers, not to variables or expressions. 3 3 USNA SP212 General Physics II DC995 DC995-Apr29-14-46-51 2007-04-29 15:47:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II (= power_TRANSMITTER_1 (DNUM 280 kW)) DC995 DC995-Apr29-14-46-51 2007-04-29 15:47:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 64 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC995 DC995-Apr29-14-46-51 2007-04-29 15:47:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II (= power_TRANSMITTER_1 (DNUM 280 kW)) DC995 DC995-Apr29-14-46-51 2007-04-29 15:47:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 9 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DC995 DC995-Apr29-14-46-51 2007-04-29 15:48:06.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 10 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=94 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC995 DC995-Apr29-14-48-25 2007-04-29 15:49:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC995 DC995-Apr29-14-48-25 2007-04-29 15:49:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DC995 DC995-Apr29-14-48-25 2007-04-29 15:50:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC995 DC995-Apr29-14-51-57 2007-04-29 15:52:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-7 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DC995 DC995-Apr29-14-51-57 2007-04-29 15:52:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 CORRECT Var-7 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 53 DC995 DC995-Apr29-14-51-57 2007-04-29 15:52:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-8 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC995 DC995-Apr29-14-51-57 2007-04-29 15:52:51.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=98 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:45:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:45:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:46:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:46:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= ampE_WAVE (* ampM_WAVE c)) DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:47:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DC9B9 DC9B9-May07-22-44-50 2007-05-07 23:47:09.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:48:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:48:47.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=234 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:48:59.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:49:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:49:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:49:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DC9B9 DC9B9-May07-22-47-39 2007-05-07 23:49:53.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 100 DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:51:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=all sources;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:51:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:51:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 23 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:12.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT 0 "P=I*A" DRAW-UNROTATED-AXES USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:29.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:46.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT System-6 label="s";body=collector;time=NIL DEFINE-POWER-VAR USNA SP212 General Physics II 22 DC9B9 DC9B9-May07-22-50-34 2007-05-07 23:59:52.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT 0 What equation do you wish to write? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:00:02.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Equations of that type appear within the problem solution. You should write the equation in the form P = I*A using your own variables. If you do not want to write this equation and are not sure what to do, why don't you call Light-Bulb-Help. 2 2 DEFINE-POWER-VAR USNA SP212 General Physics II 17 DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:00:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 INCORRECT 0 "P=I*A" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:00:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:00:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:00:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:01:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 CORRECT Var-7 label="Pc";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:01:25.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "Pc=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 61 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:01:31.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "Pc=.28P" Syntax error in Pc=.28P 1 GIVEN-FRACTION USNA SP212 General Physics II ? DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:01:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 1 "Pc=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:01:39.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 1 What equation do you wish to write? 1 GIVEN-FRACTION USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:02:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 ".28*Pc=P" GIVEN-FRACTION USNA SP212 General Physics II (= (* 0.28 power_COLLECTOR_SUNLIGHT_1) power_ELECTRIC_OUTPUT_COLLECTOR_1) DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:02:07.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:02:21.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DC9B9 DC9B9-May07-22-50-34 2007-05-08 00:02:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 92 DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:04:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:04:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:04:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 INCORRECT 0 "P=I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 12 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:05:00.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT 0 What equation do you wish to write? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:06:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:06:39.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:07:23.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 INCORRECT 0 "P=(2*!)/c" Syntax error in P=(2* )/c 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 10 ? DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:07:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 CORRECT 0 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 30 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:07:33.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:07:39.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 " 8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 47 DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:07:50.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 INCORRECT 2 "P=I*A" Undefined variable: A 1 DEFINE-AREA USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:09:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:09:40.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT 2 "P=I*A" Units are inconsistent. 1 1 DRAW-BODY USNA SP212 General Physics II (= Pr_SAIL (* int_SAIL_SUNLIGHT_1 A_SAIL)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:09:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:10:13.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-5 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 58 DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:10:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=Unspecified;forcetype=Applied;time=T0;dir=NIL;mag=59 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:10:39.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-6 label=F Andes' solution does not mention any forces on the sail due to an unspecified agent, nor any applied forces on the sail. Either this force does not exist or it is not needed for solving this problem. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:10:56.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=59 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:11:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 2 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 67 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:11:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 86 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:11:20.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DC9B9 DC9B9-May07-23-03-02 2007-05-08 00:11:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 97 DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:13:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:14:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 2 3))) 1 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T1 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:14:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 1 CORRECT 0 "c=s/t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 38 (= c (/ dist_PULSE_23 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:14:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 1 CORRECT 0 "c=s/t" WRITE-SDD USNA SP212 General Physics II 38 (= c (/ dist_PULSE_23 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:14:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 1 "t" USNA SP212 General Physics II DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:14:35.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 INCORRECT Answer-1 "1.280886125560904 s" DEFINE-DURATION USNA SP212 General Physics II DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-3 label="tt";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 2 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 2 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 1 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= t_13 (+ t_12 t_23))) 1 CORRECT 1 "tt=2*t" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-TIMES USNA SP212 General Physics II 55 (= t_13 (* 2 t_23)) DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 2 "tt" USNA SP212 General Physics II DC9B9 DC9B9-May07-23-12-16 2007-05-08 00:15:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 83 DCB03 DCB03-May07-21-05-13 2007-05-07 22:05:49.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCB03 DCB03-May07-21-05-13 2007-05-07 22:06:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DCB03 DCB03-May07-21-05-13 2007-05-07 22:06:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DCB03 DCB03-May07-21-05-13 2007-05-07 22:06:23.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 INCORRECT Answer-1 "120 V/m" Units are inconsistent. 1 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCB03 DCB03-May07-21-05-13 2007-05-07 22:07:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= ampE_WAVE (* ampM_WAVE c)) DCB03 DCB03-May07-21-05-13 2007-05-07 22:07:38.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCB03 DCB03-May07-21-05-13 2007-05-07 22:07:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 95 DCB03 DCB03-May07-21-08-09 2007-05-07 22:09:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=earth;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:09:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 3 DCB03 DCB03-May07-21-08-09 2007-05-07 22:10:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 14 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:31.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE) 3 CORRECT System-4 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:53.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-7 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:11:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 CORRECT Var-8 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 19 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:24.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT A good step would be introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:12:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II 14 DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-9 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II 9 DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-11 label="stot";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "stot=s+s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:13:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and stot is the distance travelled, and t is the duration of the trip, write v=stot/t. 6 6 WRITE-SDD USNA SP212 General Physics II 4 DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 1 "v=stot/t" WRITE-SDD USNA SP212 General Physics II 48 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 INCORRECT 2 "t" Unable to solve for t. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 43 DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:20.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 2 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:23.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "t" USNA SP212 General Physics II DCB03 DCB03-May07-21-08-09 2007-05-07 22:14:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 " 2.5617722511218077 s" USNA SP212 General Physics II 74 DCB03 DCB03-May07-21-14-54 2007-05-07 22:15:08.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DCB03 DCB03-May07-21-14-54 2007-05-07 22:15:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:11.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=238 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:35.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:43.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT straight-wire-bfield No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT (charge-force-bfield ((?axis . z))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Your goal should be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:16:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 20 DCB03 DCB03-May07-21-14-54 2007-05-07 22:17:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:17:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:17:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:17:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 15 DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:09.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER) 5 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:19.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P) 3 CORRECT System-7 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 10 DCB03 DCB03-May07-21-14-54 2007-05-07 22:18:48.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 54 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCB03 DCB03-May07-21-14-54 2007-05-07 22:19:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 49 DCB03 DCB03-May07-21-14-54 2007-05-07 22:19:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DCB03 DCB03-May07-21-14-54 2007-05-07 22:19:15.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 80 DCB03 DCB03-May07-21-19-36 2007-05-07 22:20:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:20:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:20:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=all forces;time=T0;value="2.0 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:20:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:20:51.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 2 DCB03 DCB03-May07-21-19-36 2007-05-07 22:21:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCB03 DCB03-May07-21-19-36 2007-05-07 22:21:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:21:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Try introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:21:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 7 DCB03 DCB03-May07-21-19-36 2007-05-07 22:21:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-6 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 17 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:33.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:50.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT (charge-force-bfield ((?axis . z))) No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:51.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT electric-dipole-moment-mag No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:22:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 12 DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-8 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 13 DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Ps = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 8 DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:53.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Ps=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 52 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:23:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Ps 3 3 GIVEN-FRACTION USNA SP212 General Physics II 47 DCB03 DCB03-May07-21-19-36 2007-05-07 22:24:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCB03 DCB03-May07-21-19-36 2007-05-07 22:24:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 42 DCB03 DCB03-May07-21-19-36 2007-05-07 22:24:12.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DCB03 DCB03-May07-21-19-36 2007-05-07 22:24:18.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 73 DCB03 DCB03-May07-21-27-03 2007-05-07 22:28:45.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DEFINE-INTENSITY USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:29:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 12 DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 7 DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:57.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL) 3 CORRECT System-4 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 19 DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:30:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Your goal should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:31:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:31:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:31:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 14 DCB03 DCB03-May07-21-27-03 2007-05-07 22:31:15.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=103 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 9 DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 17 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:53.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT coulomb No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT You should be introducing a variable for the pressure at the sail at T0. 5 DEFINE-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT (net-field-electric ((?axis . x))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 DEFINE-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:32:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 HINT Define a variable for the pressure at the sail at T0 by using the Add Variable command on the Variable menu and selecting Pressure. 6 6 DEFINE-PRESSURE USNA SP212 General Physics II 12 DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 CORRECT Var-6 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 13 DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 8 DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 27 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:33:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 22 DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 42 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 37 DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 3 "A" USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "P" USNA SP212 General Physics II DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:24.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 53 DCB03 DCB03-May07-21-27-03 2007-05-07 22:34:25.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 64 DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:10:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:10:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:10:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 3 3 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:17:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 20 (= ampE_WAVE (DNUM 120 V/m)) DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:17:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 22:18:00.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:16:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:16:32.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 4 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:19:59.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 INCORRECT Answer-1 "120" Forgot to put units on a number. 1 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:20:07.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 2 INCORRECT Answer-1 "120 V" Units are inconsistent. 1 1 USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:20:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 3 INCORRECT Answer-1 "120 T" USNA SP212 General Physics II DCB21 DCB21-Apr13-21-09-51 2007-04-13 23:22:48.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 4 CORRECT Answer-1 "4e-7 T" USNA SP212 General Physics II 47 DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:10:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:10:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:10:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:10:55.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:11:30.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:11:43.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:11:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:11:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:11:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E = c * B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:12:00.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-09-54 2007-04-18 17:12:03.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 95 DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:11.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-1 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=234 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 6 DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:46.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:13:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:00.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:18.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:52.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 CORRECT System-5 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:14:58.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:15:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:15:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:15:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 INCORRECT 1 "I = P/(4/3 * $p * r^3)" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 24 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* (/ 4 3) $P) (^ r_P_TRANSMITTER_1 3)))) DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 7 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 8 CORRECT 1 "P= 4 * $p * r^2 * I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 68 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-12-51 2007-04-18 17:16:32.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 99 DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:23:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:23:58.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:24:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:24:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 25 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:27.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:43.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:46.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT intensity-to-decibels No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:25:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 CORRECT Var-4 label="Pc";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT A good step would be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:38.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 0 "I = Pc/A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= int_COLLECTOR_SUNLIGHT_1 (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:26:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:27:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Pc 3 3 GIVEN-FRACTION USNA SP212 General Physics II 64 DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:27:12.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P = .28 * Pc" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:27:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-17-36 2007-04-18 17:27:23.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 95 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:27:53.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DEFINE-INTENSITY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:28:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:28:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:28:44.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 CORRECT System-3 label="Sa";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 23 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:28:50.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 INCORRECT System-4 label="Su";body=sunlight;time=NIL DRAW-BODY USNA SP212 General Physics II 22 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:28:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:29:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 CORRECT Var-5 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 23 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:29:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:29:45.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-7 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=40 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:29:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F = 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 32 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:05.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:17.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:20.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT intensity-to-decibels No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 27 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 CORRECT 1 "P = (2 * I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 47 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:52.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:30:56.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 63 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:31:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:31:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 58 DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:31:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 3 "F = P * A" PRESSURE-FORCE USNA SP212 General Physics II 78 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:31:15.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-27-46 2007-04-18 17:31:19.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 89 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:31:52.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:31:58.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-2 label="E";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II 3 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:32:37.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II 2 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:32:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 CORRECT Var-4 label="st";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 3 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:33:06.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 M" Syntax error in s1=3.84e8 M 1 DEFINE-DISTANCE USNA SP212 General Physics II ? DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:33:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 12 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:33:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 CORRECT Var-6 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 22 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:33:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s1 + s2 = st" WRITE-SUM-DISTANCES USNA SP212 General Physics II 23 (= (+ dist_PULSE_12 dist_PULSE_23) dist_PULSE_13) DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:33:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:34:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:34:21.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-8 label="m";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:34:27.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 CORRECT System-9 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:34:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:34:36.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 3 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:10.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 4 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 6 HINT Try introducing a variable for the speed of the pulse. 6 DEFINE-WAVE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 7 INCORRECT Var-10 label="v";quant=speed;subtype=instantaneous;body=pulse;agent=NIL;time=T0;value="" DEFINE-WAVE-SPEED USNA SP212 General Physics II 22 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-SPEED USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:35:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 CORRECT Var-11 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II 23 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:03.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "st = v * t" WRITE-SDD USNA SP212 General Physics II 67 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 62 DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 2 "v = c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "t" USNA SP212 General Physics II DCBF9 DCBF9-Apr18-16-31-36 2007-04-18 17:36:34.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 93 DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:46:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:46:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:46:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 3 3 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:47:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 20 (= ampE_WAVE (DNUM 120 V/m)) DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:47:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:47:21.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:47:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:48:57.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:00.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 5 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 HINT A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 6 DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 7 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 7 7 DEFINE-AMPLITUDE USNA SP212 General Physics II 15 DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 8 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 10 DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 54 (= ampE_WAVE (* c ampM_WAVE)) DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 49 DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:36.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 2 CORRECT 1 "B" USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-46-35 2007-03-26 18:49:41.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 80 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:39.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 3 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:52:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 4 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -4 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:19.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 4 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:53:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II -1 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:27.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=238 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -6 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:54:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:03.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT magnetic-dipole-torque-mag No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT (net-field-magnetic ((?axis . z))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT A good step would be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II -1 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -6 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:48.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-5 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:56:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -11 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:00.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -16 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:22.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 INCORRECT 1 "P=4*x*(r^2)*I" The variable x is not used in any solution I know of. 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 HINT 1 I can only recognize equations and variables from solutions I know about. This variable is not used in any of the solutions I have recorded for this problem. It's possible you are pursuing a solution that I don't know about, but if so, I can't help you with it and simpler solutions are probably available. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 7 INCORRECT 1 "P=4*$c*(r^2)*I" Undefined variable: $c 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -17 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:57:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 8 HINT 1 Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:17.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 9 INCORRECT 1 "P=4*pi$c*(r^2)*I" Undefined variable: pi$c 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 10 HINT 1 Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:25.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 11 INCORRECT 1 "P=4*pi*(r^2)*I" Undefined variable: pi 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -18 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 12 HINT 1 Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 13 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 26 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 21 DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-52-01 2007-03-26 18:58:58.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 53 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:48.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 18:59:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -4 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:00:57.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 4 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II -1 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 8 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:01:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:02:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT lens-combo No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:02:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT refraction-vacuum No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:02:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:02:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 3 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-4 label="P2";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 4 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Your goal should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II -1 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P2 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -6 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P2=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 38 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P2 3 3 GIVEN-FRACTION USNA SP212 General Physics II 33 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:03:59.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*P2" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:04:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 28 DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:04:08.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DCC3B DCC3B-Mar26-17-59-12 2007-03-26 19:04:12.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 59 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:09:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:09.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:23.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:10:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -9 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:13:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -11 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:13:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -1 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:13:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:13:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:13:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -6 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:14:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 4 HINT Why don't you continue working on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:14:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 5 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:14:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 6 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -11 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 7 HINT Why don't you continue working on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 8 HINT Your goal should be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 9 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -16 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 10 HINT Why don't you continue working on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:21.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s2 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -17 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -7 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:16:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:08.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:15.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:30.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT speed-equals-wave-speed That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT Try introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II -12 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-5 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Your goal should be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:17:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -17 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-6 label="s3";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Your goal should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II -22 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II -21 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and s3 is the distance travelled, and t is the duration of the trip, write v=s3/t. 6 6 WRITE-SDD USNA SP212 General Physics II -26 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 0 "v=s3/t" WRITE-SDD USNA SP212 General Physics II 18 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 13 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:48.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:18:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 4 HINT Write the equation ?T02-VAR = s + s2. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 8 DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:05.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 INCORRECT 2 "?T02-VAR=s+s2" Syntax error in T02-VAR=s+s2 1 USNA SP212 General Physics II 7 ? DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 Unknown 5 HINT The equation or the units in it are not in a recognizable form. 2 USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 Unknown 6 HINT Though I can't tell exactly what the mistake is, a few common sources of errors are: (a) Unit symbols are case sensitive. (b) Multiplication always requires an explicit multiplication sign: W=m*g, NOT W=mg. (c) Units attach only to numbers, not to variables or expressions. 3 3 USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 7 HINT Why don't you continue working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 8 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 9 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-09-46 2007-03-26 19:19:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 10 HINT Write the equation ?T02-VAR = s + s2. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:19:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:20:00.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:20:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:20:18.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:20:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:15.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 7 HINT sdd Right. You have already finished applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. You can move on to the next step in the solution. 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 8 HINT Why don't you work on calculating the sum of distances travelled by the pulse during from T0 to T2. 5 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 9 HINT Distances can be added together. 6 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 10 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 7 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 11 HINT Write the equation ?T02-VAR = s + s2. 8 8 WRITE-SUM-DISTANCES USNA SP212 General Physics II 2 DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 12 CORRECT 2 "s3=s+s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II -3 DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "t" USNA SP212 General Physics II DCC3B DCC3B-Mar26-18-19-41 2007-03-26 19:21:46.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 28 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:00:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-1 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 6 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:00:55.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:01:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:01:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 INCORRECT 0 "P = I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 11 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:02:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 INCORRECT 0 "P = I/3e8m/s" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 (DNUM 3.0e+8 m/s))) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:02:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 CORRECT 0 "P = 2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 31 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:03:24.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=79 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 30 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:03:30.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-4 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:03:44.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=79 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 31 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:03:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:04:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 1 "F = P*A" PRESSURE-FORCE USNA SP212 General Physics II 51 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:04:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:04:25.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 INCORRECT 3 "A" Unable to solve for A. One thing you probably need is an equation specifying the given value of F. 1 1 USNA SP212 General Physics II DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:04:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 3 "F = 20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 59 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:04:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:05:03.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 76 DCC4D DCC4D-Apr05-14-00-06 2007-04-05 15:05:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 87 DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:13.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:58:45.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:59:00.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:59:09.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT energy-decay No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:59:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:59:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 18 DCC4D DCC4D-Apr12-16-55-11 2007-04-12 17:59:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 62 (= ampE_WAVE (* c ampM_WAVE)) DCC4D DCC4D-Apr12-16-55-11 2007-04-12 18:00:00.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCC4D DCC4D-Apr12-16-55-11 2007-04-12 18:00:11.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:01:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:01:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 3 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:01:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8.0 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 2 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:02:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:02:14.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:02:23.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=244 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 4 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:02:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the total power produced by the transmitter at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:23.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-5 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 13 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-5 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 23 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:41.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT #.(wb-quant '(define-variable "v" |instantaneous| |speed| |transmitter| |T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT #.(wb-quant '(define-variable "g" |NIL| |gravitational-acceleration| |transmitter| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:45.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT #.(wb-quant '(define-variable "f" |NIL| |frequency| |transmitter| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the intensity supplied to P at T0 due to the transmitter. 4 4 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:46.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:07:49.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 6 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:00.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 7 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 7 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 8 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 8 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 9 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 9 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:17.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 10 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 11 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 12 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 13 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 14 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 18 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:31.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 15 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:08:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 13 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:09:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:09:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 7 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 8 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 8 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 9 CORRECT 2 "P = 4* $p * (r^2) * I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 52 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 47 DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:45.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 3 "P" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:50.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 3 CORRECT 4 "I" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-01-13 2007-04-12 18:10:54.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 78 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:11.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:38.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:12:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:13:16.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 12 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:13:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 23 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:26.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "W" |NIL| |work| |electric_output| |T0| |non-conservative forces| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:28.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT #.(wb-quant '(define-variable "NIL" |NIL| |length| |electric_output| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:31.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the area of the collector. 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:32.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:34.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:35.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 7 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 HINT Your goal should be introducing a variable for the power supplied to the collector from the sunlight at T0. 8 DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:14:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 10 CORRECT Var-4 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:15:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:15:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Try introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:15:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:16:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:16:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:16:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:16:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Ps = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 18 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Ps = A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Ps 3 3 GIVEN-FRACTION USNA SP212 General Physics II 57 DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P = .28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:18.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:23.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 INCORRECT Answer-1 "2000000 W" Units are inconsistent. 1 1 USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 3 "A" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-11-09 2007-04-12 18:17:34.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 2 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 85 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:42.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-2 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:52.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 INCORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 9 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:18:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 3 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:12.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 3 INCORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 8 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 4 INCORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.2kW/m^2" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= int_SAIL_SUNLIGHT_1 (DNUM 1.2 kW/m^2)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 5 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 17 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 CORRECT Var-6 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:19:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 12 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:20:44.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 11 INCORRECT Vector-8 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=359;mag=279 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:00.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 12 CORRECT Vector-8 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=279 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 CORRECT 0 "F = 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 21 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:26.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:21:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 16 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 11 CORRECT 1 "P = (2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 36 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT Try introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 CORRECT Var-9 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:31.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 INCORRECT 2 "P = A * I" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II 35 (= Pr_SAIL (* A_SAIL int_SAIL_SUNLIGHT_1)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 30 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:48.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 5 CORRECT 2 "F = P * A" PRESSURE-FORCE USNA SP212 General Physics II 50 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 45 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:22:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 5 CORRECT 3 "F" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:23:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 6 CORRECT 4 "A" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:23:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 7 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 62 DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:23:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 8 CORRECT 5 "P" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-17-52 2007-04-12 18:23:12.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 2 CORRECT Answer-1 " 8.672666475151953e-6 Pa" USNA SP212 General Physics II 73 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:24:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:24:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:24:58.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:06.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:19.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -1 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.8e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -2 (= dist_PULSE_12 (DNUM 3.8e+8 m)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:25:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 8 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:16.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s2 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 17 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 CORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 18 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:34.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "T" |NIL| |period| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:36.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "T" |NIL| |period| |earth| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT #.(wb-quant '(define-variable "v" |average| |speed| |moon| |T1 to T2| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the duration of the interval from T0 to T2. 4 4 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:44.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:48.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 7 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 8 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:26:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 9 HINT A good step would be introducing a variable for the speed of the pulse. 9 DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:27:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 10 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 10 10 DEFINE-SPEED USNA SP212 General Physics II 13 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:27:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 11 CORRECT Var-5 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:27:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:27:53.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 INCORRECT 0 "s1 = v*T1" Undefined variable: T1 1 DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 6 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II 8 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 7 CORRECT Var-6 label="s3";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 2 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 3 HINT You should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II 3 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 5 CORRECT Var-7 label="t01";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T1;value="" DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 1 CORRECT 0 "s1 = v*t01" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II 25 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_12)) 1 CORRECT 0 "s1 = v*t01" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II 25 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:28:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 0 "s1 = v*t01" WRITE-SDD USNA SP212 General Physics II 25 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-9 label="t02";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 INCORRECT 1 "s2 = v*t02" WRITE-SDD USNA SP212 General Physics II (= dist_PULSE_23 (* sp_PULSE_13 t_13)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 CORRECT 1 "s3 = v*t02" WRITE-SDD USNA SP212 General Physics II 47 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 2 3))) 1 CORRECT Var-10 label="t03";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T1 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_23)) 1 CORRECT 2 "s2 = v*t03" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= dist_PULSE_23 (* sp_PULSE_13 t_23)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 1 CORRECT 2 "s2 = v*t03" WRITE-SDD USNA SP212 General Physics II (= dist_PULSE_23 (* sp_PULSE_13 t_23)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 2 CORRECT 2 "s2 = v*t03" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= dist_PULSE_23 (* sp_PULSE_13 t_23)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:29:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 42 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:07.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 3 "v = c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 4 "s2" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:23.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 5 "t03" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 INCORRECT Answer-1 "1.280886125560904 s" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 4 INCORRECT 6 "t02" Unable to solve for t02. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Write the equation ?T02-VAR = s1 + s2. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 37 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:30:46.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 INCORRECT 6 "t02 = s1 + s2" Units are inconsistent. 1 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II (= t_13 (+ dist_PULSE_12 dist_PULSE_23)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 CORRECT 6 "s3 = s1 + s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 5 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 32 DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 6 CORRECT 7 "t03" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 7 CORRECT 8 "s2" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:26.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 8 CORRECT 9 "t03" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:29.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 9 CORRECT 10 "t02" USNA SP212 General Physics II DCC4D DCC4D-Apr12-17-23-31 2007-04-12 18:31:34.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 60 DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:28:22.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:28:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:29:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:31:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:31:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:23.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT wave-speed-light No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 18 DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 62 (= ampE_WAVE (* c ampM_WAVE)) DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:47.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-27-45 2007-04-09 00:36:54.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 " 4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:38:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8.0km" DEFINE-NET-POWER-OUT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:38:21.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 HINT Var-1 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:00.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kw" Syntax error in P=280kw 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II ? DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:07.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 HINT Var-2 label=P Syntax error in P=280kw 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 5 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 11 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:29.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:39:50.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 CORRECT System-4 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 13 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:40:08.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 1 INCORRECT 0 "p_x=8.0km" Undefined variable: p_x 1 DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 12 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:40:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 2 INCORRECT Var-5 label="p_x";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8.0km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:40:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 INCORRECT Var-6 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:40:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:40:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT Try introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 7 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:21.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 6 CORRECT Vector-7 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=245 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:24.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 INCORRECT 0 "_x=8.0km" Syntax error in _x=8.0km 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II ? DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 INCORRECT 0 "r_x=8.0km" The variable r_x is not used in any solution I know of. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 CORRECT 0 "r=8.0km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:41:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:42:12.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:42:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT wave-speed-light No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:42:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:42:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 CORRECT Var-8 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 17 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 12 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:26.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-9 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:43:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 7 DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:44:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 51 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:44:16.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-37-23 2007-04-09 00:44:23.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 82 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=electric_output;agent=all sources;time=T0;value="960 W/m^2" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:33.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:52.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:46:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -7 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 4 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II -1 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:47:58.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -3 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:48:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0MW" DEFINE-POWER-VAR USNA SP212 General Physics II 8 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:48:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:48:25.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:20.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:21.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT energy-decay No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 3 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:49:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue working on relating the intensity to power (uniform intensity). 1 GIVEN-FRACTION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 0 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Your goal should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -2 DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:50:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 1 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 42 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:51:02.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-44-51 2007-04-09 00:51:09.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 74 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:52:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:14.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-BODY USNA SP212 General Physics II 11 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 6 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:31.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-5 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 18 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:53:51.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 INCORRECT Var-6 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="20mN" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-PRESSURE USNA SP212 General Physics II 17 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 CORRECT Var-6 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 18 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:54:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 13 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:16.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 CORRECT Vector-9 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=72 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 22 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:39.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Yep. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:46.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:48.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT harmonic-of No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:55:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 17 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:56:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 INCORRECT 1 "P=(2*I)/C" Undefined variable: C 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 16 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:56:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 36 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:56:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:56:31.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 53 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:56:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT A good step would be introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 HINT Define a variable for the area of the sail by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 48 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 5 CORRECT Var-10 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 43 DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 62 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:47.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-51-27 2007-04-09 00:57:54.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 73 DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:18.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Var-1 label=s Are you sure you want the variable defined at T1? 1 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Although you need a variable for the distance, no solution I know of needs it at T1. Clicking on the light bulb button will may help you figure out an overall solution plan. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:46.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 00:59:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:02.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-2 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -3 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:19.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 HINT A good step would be introducing a variable for the distance travelled by the pulse from T0 to T1. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -7 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 5 CORRECT Var-5 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 2 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:00:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:02.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 INCORRECT Var-6 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 HINT Why don't you continue working on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 5 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -3 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 6 CORRECT Var-6 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 7 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:44.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:01:57.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:00.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT You should be introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II 2 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-7 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 6 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 7 HINT You should be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 8 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -3 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 9 CORRECT Var-8 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II -2 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:02:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT Your goal should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II -7 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-9 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and s2 is the distance travelled, and t is the duration of the trip, write v=s2/t. 6 6 WRITE-SDD USNA SP212 General Physics II -12 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 0 "v=s2/t" WRITE-SDD USNA SP212 General Physics II 32 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 27 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:03:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 22 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:04:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 INCORRECT 2 "?T02-VAR=s+s1" Syntax error in T02-VAR=s+s1 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II ? DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:04:30.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 INCORRECT 2 "T02-VAR=s+s1" Undefined variables: (T02 VAR) 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 21 DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:04:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 7 CORRECT 2 "s2=s+s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:04:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "t" USNA SP212 General Physics II DCD19 DCD19-Apr08-23-58-11 2007-04-09 01:05:04.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 53 DCDA9 DCDA9-Apr05-10-52-57 2007-04-05 11:53:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DCDA9 DCDA9-Apr05-10-52-57 2007-04-05 11:53:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DCDA9 DCDA9-Apr05-10-52-57 2007-04-05 11:53:59.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B= c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= (/ ampE_WAVE ampM_WAVE) c) DCDA9 DCDA9-Apr05-10-52-57 2007-04-05 11:54:04.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCDA9 DCDA9-Apr05-10-52-57 2007-04-05 11:54:11.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DCDA9 DCDA9-Apr05-11-40-16 2007-04-05 12:41:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 6 DCDA9 DCDA9-Apr05-11-40-16 2007-04-05 12:41:16.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II 3 DCDA9 DCDA9-Apr05-11-40-16 2007-04-05 12:41:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 4 DCDA9 DCDA9-Apr05-11-40-16 2007-04-05 12:41:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 INCORRECT 0 "s= 3.84 e8 m" USNA SP212 General Physics II 3 (= dist_PULSE_13 (DNUM 3.84e+8 m)) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:35:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 CORRECT 0 "s=2* 3.84 e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= dist_PULSE_13 (* (* 2 3.84e+8) (DNUM 1 m))) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:35:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 0 "s=2* 3.84 e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= dist_PULSE_13 (* (* 2 3.84e+8) (DNUM 1 m))) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:35:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s=2* 3.84 e8 m" WRITE-SUM-DISTANCES USNA SP212 General Physics II 16 (= dist_PULSE_13 (* (* 2 3.84e+8) (DNUM 1 m))) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:35:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DEFINE-DURATION USNA SP212 General Physics II DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:36:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 17 DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:36:09.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 INCORRECT 1 "c= s*t" Units are inconsistent. 1 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 16 (= c (* dist_PULSE_13 t_13)) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:36:52.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 1 "c*t= s" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 60 (= (* c t_13) dist_PULSE_13) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:36:52.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "c*t= s" WRITE-SDD USNA SP212 General Physics II 60 (= (* c t_13) dist_PULSE_13) DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:36:57.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DCDA9 DCDA9-Apr05-13-34-11 2007-04-05 14:37:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 91 DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:42:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 KW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 9 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 KW/m^2)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:43:52.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 INCORRECT 1 "P= I/c" Undefined variable: P 1 DEFINE-PRESSURE USNA SP212 General Physics II DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 CORRECT Var-6 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 10 DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 1 INCORRECT 1 "P= I/c" USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 2 INCORRECT 1 "P= I/c" USNA SP212 General Physics II 9 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 3 INCORRECT 1 "P= I/c" USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 4 INCORRECT 1 "P= I/c" USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:38.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 5 INCORRECT 1 "P= I/c" USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 0 1 INCORRECT 0 "P= I/c" USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DCDA9 DCDA9-Apr05-13-41-50 2007-04-05 14:44:50.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE5 0 2 HINT 0 What equation do you wish to write? 1 USNA SP212 General Physics II DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:07:08.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 INCORRECT 0 "P= 2I/c" Syntax error in P= 2I/c 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II ? DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:07:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 0 "P= 2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 29 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:07:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:07:41.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 45 DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:08:36.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-7 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=85 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 46 DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:08:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-8 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:08:56.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 CORRECT Vector-7 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=85 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:09:03.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 2 "F= 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 54 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:09:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "P= F/A" PRESSURE-FORCE USNA SP212 General Physics II 74 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:09:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:09:22.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 85 DCDA9 DCDA9-Apr17-16-06-20 2007-04-17 17:09:51.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 5 1 INCORRECT 5 "radiatiion pressure is twice b/c it is a perfect reflector" Syntax error in radiatiion pressure is twice b/c it is a perfect reflector 1 USNA SP212 General Physics II ? DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:11:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:11:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:11:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:11:59.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:12:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:30.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 7 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 8 HINT A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 5 DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 9 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 6 6 DEFINE-AMPLITUDE USNA SP212 General Physics II 20 DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 10 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 CORRECT 0 "B=E/c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampM_WAVE (/ ampE_WAVE c)) DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:13:59.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:14:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 CORRECT Answer-1 "4.0027691423778244e-7 T" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 95 DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:14:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 2 CORRECT 1 "B = 4.0027691423778244e-7 T" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= ampM_WAVE (DNUM 4.0027691423778244e-7 T)) DCE39 DCE39-Apr29-21-10-49 2007-04-29 22:14:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 CORRECT 1 "B = 4.0027691423778244e-7 T" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II (= ampM_WAVE (DNUM 4.0027691423778244e-7 T)) DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:26:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8.0km" DEFINE-NET-POWER-OUT USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:26:22.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 HINT Var-1 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:26:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 12 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:27:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 1 INCORRECT Var-3 label="p";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8.0km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 11 DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:27:48.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT Var-3 label=p This problem should be solved by drawing relative position vectors. Although the length you've defined might have the same value as the magnitude of a relative position, it is an Andes convention to use quantities that appear in the principles whenever possible. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:28:03.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=228 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 12 DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:28:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:28:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:29:40.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:29:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCE39 DCE39-Apr29-21-25-57 2007-04-29 22:30:44.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCE39 DCE39-Apr29-21-42-39 2007-04-29 22:44:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCE39 DCE39-Apr29-21-42-39 2007-04-29 22:44:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 4 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCE39 DCE39-Apr29-21-42-39 2007-04-29 22:50:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 5 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCE39 DCE39-Apr29-21-42-39 2007-04-29 22:50:51.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 6 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:11:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:11:41.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:12:06.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT radiation-pressure No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:12:46.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT amperes-law No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:12:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:12:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 18 DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-6 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 13 DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:32.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-7 label="T";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:37.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-8 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 14 DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:13:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:14:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:14:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 9 DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:14:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 53 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:14:27.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DCE39 DCE39-Apr30-09-11-28 2007-04-30 10:14:35.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 84 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="2.0MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:19.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:33.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=P why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:52.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2.0MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II 2 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:21:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 3 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:22:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT Why don't you continue working on entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 1 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:22:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:23:12.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2.0MW" Units are inconsistent. 1 1 DEFINE-INTENSITY USNA SP212 General Physics II (= int_COLLECTOR_SUNLIGHT_1 (DNUM 2.0 MW)) DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:23:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:23:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:23:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Try introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 CORRECT Var-6 label="Pe";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0MW" DEFINE-POWER-VAR USNA SP212 General Physics II 22 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AREA USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:14.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AREA USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:39.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT radiation-pressure No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AREA USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:49.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 HINT energy-decay No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-AREA USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 5 HINT A good step would be introducing a variable for the area of the collector. 5 DEFINE-AREA USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 6 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 6 6 DEFINE-AREA USNA SP212 General Physics II 17 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:24:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 7 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 18 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:21.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 0 "I=P/A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= int_COLLECTOR_SUNLIGHT_1 (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation Pe = 0.28 * P 3 3 GIVEN-FRACTION USNA SP212 General Physics II 57 DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:25:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "Pe=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:27:34.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DCE39 DCE39-Apr30-09-19-57 2007-04-30 10:27:39.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 88 DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:38:20.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:38:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1;value="3.84e8" DEFINE-DISTANCE USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:38:56.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Var-3 label=s1 Are you sure you want the variable defined at T1? 1 DEFINE-DISTANCE USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Although you need a variable for the distance, no solution I know of needs it at T1. Clicking on the light bulb button will may help you figure out an overall solution plan. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT If you click on 'explain more', I'll tell you a correct entry to make. However, you'd learn more if you figure it out yourself, perhaps with the aid of the light bulb button's hints. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 HINT Define a variable for the distance from T0 to T2 instead of at T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -5 DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:49.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 6 INCORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8" The value of s1 is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 7 CORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II -3 DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:39:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:40:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -8 DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:41:02.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-4 label="l";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -7 DCE39 DCE39-Apr30-09-35-59 2007-04-30 10:41:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:30:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DCECF DCECF-May06-15-29-04 2007-05-06 16:30:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DCECF DCECF-May06-15-29-04 2007-05-06 16:31:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:31:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:31:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:31:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:31:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 5 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:31:43.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 6 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:33:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 7 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:33:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 8 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:33:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 9 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:33:34.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 0 1 INCORRECT 0 "B=E" Units are inconsistent. 1 1 USNA SP212 General Physics II 23 (= ampM_WAVE ampE_WAVE) DCECF DCECF-May06-15-29-04 2007-05-06 16:33:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 10 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:33:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 Unknown 11 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DCECF DCECF-May06-15-29-04 2007-05-06 16:39:53.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Vector-3 1 INCORRECT Vector-3 label="v";type=Velocity;body=wave;agent=instantaneous;time=NIL;dir=0;mag=190 USNA SP212 General Physics II 21 DCECF DCECF-May06-15-29-04 2007-05-06 16:39:55.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE1 Vector-3 2 HINT Vector-3 label=v None of the solutions that I know include a velocity vector. Try clicking on the light bulb button or 'explain further' for suggestions about another approach. 1 USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:33:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:33:15.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT Var-1 label=s Are you sure you want the variable defined at T1? 1 DEFINE-DISTANCE USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:33:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 HINT Although you need a variable for the distance, no solution I know of needs it at T1. Clicking on the light bulb button will may help you figure out an overall solution plan. 2 DEFINE-DISTANCE USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:33:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 HINT If you click on 'explain more', I'll tell you a correct entry to make. However, you'd learn more if you figure it out yourself, perhaps with the aid of the light bulb button's hints. 3 DEFINE-DISTANCE USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:33:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 5 HINT Define a variable for the distance from T1 to T2 instead of at T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -5 DCECF DCECF-May07-17-32-26 2007-05-07 18:33:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 6 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 8 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-2 label="t1";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 9 DCECF DCECF-May07-17-32-26 2007-05-07 18:34:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 2 3))) 1 CORRECT Var-3 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T1 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:34:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 1 CORRECT 0 "c=s/t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 31 (= c (/ dist_PULSE_23 t_23)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 1 CORRECT 0 "c=s/t" WRITE-SDD USNA SP212 General Physics II 31 (= c (/ dist_PULSE_23 t_23)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 2 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 2 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 1 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:34:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= t_13 (+ t_12 t_23))) 1 CORRECT 1 "t1=t*2" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-TIMES USNA SP212 General Physics II 50 (= t_13 (* t_23 2)) DCECF DCECF-May07-17-32-26 2007-05-07 18:35:05.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t1" USNA SP212 General Physics II DCECF DCECF-May07-17-32-26 2007-05-07 18:35:12.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 " 2.5617722511218077 s" USNA SP212 General Physics II 81 DCECF DCECF-May07-21-54-22 2007-05-07 22:54:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 66 (= ampE_WAVE (* ampM_WAVE c)) DCECF DCECF-May07-21-54-22 2007-05-07 22:55:07.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DCECF DCECF-May07-21-54-22 2007-05-07 22:55:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 97 DCECF DCECF-May07-21-55-28 2007-05-07 22:56:22.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=238 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 6 DCECF DCECF-May07-21-55-28 2007-05-07 22:56:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DCECF DCECF-May07-21-55-28 2007-05-07 22:56:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DCECF DCECF-May07-21-55-28 2007-05-07 22:57:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DCECF DCECF-May07-21-55-28 2007-05-07 22:58:03.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 INCORRECT 2 "I" Unable to solve for I. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DCECF DCECF-May07-21-55-28 2007-05-07 22:58:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DCECF DCECF-May07-21-55-28 2007-05-07 22:58:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DCECF DCECF-May07-21-55-28 2007-05-07 22:58:37.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 100 DCECF DCECF-May07-22-11-33 2007-05-07 23:12:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DCECF DCECF-May07-22-11-33 2007-05-07 23:12:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DCECF DCECF-May07-22-11-33 2007-05-07 23:12:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 25 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DCECF DCECF-May07-22-11-33 2007-05-07 23:12:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DCECF DCECF-May07-22-11-33 2007-05-07 23:13:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCECF DCECF-May07-22-11-33 2007-05-07 23:13:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 "P1=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DCECF DCECF-May07-22-11-33 2007-05-07 23:13:38.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DCECF DCECF-May07-22-11-33 2007-05-07 23:13:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 100 DCECF DCECF-May07-22-14-16 2007-05-07 23:14:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 KW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 KW/m^2)) DCECF DCECF-May07-22-14-16 2007-05-07 23:14:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:15:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:15:17.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=55 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:15:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 0 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 33 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DCECF DCECF-May07-22-14-16 2007-05-07 23:16:15.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 INCORRECT 1 "F=2*I*c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 32 (= Fp_SAIL_SUNLIGHT_1 (* (* 2 int_SAIL_SUNLIGHT_1) c)) DCECF DCECF-May07-22-14-16 2007-05-07 23:16:29.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 INCORRECT 1 "F=2*I/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCECF DCECF-May07-22-14-16 2007-05-07 23:17:01.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 INCORRECT 1 "F=(2*I)/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 31 (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCECF DCECF-May07-22-14-16 2007-05-07 23:17:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:17:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 51 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DCECF DCECF-May07-22-14-16 2007-05-07 23:17:29.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 INCORRECT 2 "A" Unable to solve for A. One thing you probably need is an equation specifying the given value of F. 1 1 USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:17:34.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 2 "P" USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:17:41.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 68 DCECF DCECF-May07-22-14-16 2007-05-07 23:18:01.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 CORRECT 3 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 76 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DCECF DCECF-May07-22-14-16 2007-05-07 23:18:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DCECF DCECF-May07-22-14-16 2007-05-07 23:18:12.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 87 DD037 DD037-May07-11-33-47 2007-05-07 12:35:18.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Answer-1 "120 V" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:24.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 INCORRECT Answer-1 "120 V/M" This expression contains variables not allowed in the answer: (M) 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:30.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 INCORRECT Answer-1 "120 V/m" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 5 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 6 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 7 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:36:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 8 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD037 DD037-May07-11-33-47 2007-05-07 12:36:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:36:21.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:36:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT electromagnetic-wave-field-amplitude Right. A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:36:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 4 4 DEFINE-AMPLITUDE USNA SP212 General Physics II 20 DD037 DD037-May07-11-33-47 2007-05-07 12:37:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 CORRECT Var-3 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:37:32.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* ampM_WAVE c)) DD037 DD037-May07-11-33-47 2007-05-07 12:37:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD037 DD037-May07-11-33-47 2007-05-07 12:37:45.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 90 DD037 DD037-May07-11-38-17 2007-05-07 12:47:28.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 INCORRECT Var-1 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="c" The value of v is not given in this problem. It should be marked unknown. 1 1 DEFINE-SPEED USNA SP212 General Physics II DD037 DD037-May07-11-38-17 2007-05-07 12:48:04.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DD037 DD037-May07-11-38-17 2007-05-07 12:48:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 11 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD037 DD037-May07-11-38-17 2007-05-07 12:48:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-3 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 12 DD037 DD037-May07-11-38-17 2007-05-07 12:48:44.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 INCORRECT 0 "s2=2*2" Units are inconsistent. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_13 (* 2 2)) DD037 DD037-May07-11-38-17 2007-05-07 12:48:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 CORRECT 0 "s2=2*s" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 19 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD037 DD037-May07-11-38-17 2007-05-07 12:48:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 0 "s2=2*s" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 19 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD037 DD037-May07-11-38-17 2007-05-07 12:48:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s2=2*s" WRITE-SUM-DISTANCES USNA SP212 General Physics II 19 (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD037 DD037-May07-11-38-17 2007-05-07 12:49:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-4 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD037 DD037-May07-11-38-17 2007-05-07 12:49:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 1 "s2=c*t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 63 (= dist_PULSE_13 (* c t_13)) DD037 DD037-May07-11-38-17 2007-05-07 12:49:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "s2=c*t" WRITE-SDD USNA SP212 General Physics II 63 (= dist_PULSE_13 (* c t_13)) DD037 DD037-May07-11-38-17 2007-05-07 12:49:49.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DD037 DD037-May07-11-38-17 2007-05-07 12:49:53.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 95 DD037 DD037-May07-11-50-11 2007-05-07 12:50:48.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=228 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 6 DD037 DD037-May07-11-50-11 2007-05-07 12:50:53.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD037 DD037-May07-11-50-11 2007-05-07 12:51:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD037 DD037-May07-11-50-11 2007-05-07 12:52:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:52:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT 1 "I=4/3*$p*r^4" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II 24 (= int_P_TRANSMITTER_1 (* (* (/ 4 3) $P) (^ r_P_TRANSMITTER_1 4))) DD037 DD037-May07-11-50-11 2007-05-07 12:52:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 INCORRECT 1 "I=4/3*$p*r^3" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II 23 (= int_P_TRANSMITTER_1 (* (* (/ 4 3) $P) (^ r_P_TRANSMITTER_1 3))) DD037 DD037-May07-11-50-11 2007-05-07 12:53:09.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:53:16.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 23 DD037 DD037-May07-11-50-11 2007-05-07 12:53:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:53:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:55:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT electric-flux-constant-field No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:55:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT (net-field-electric ((?axis . x))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:55:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:55:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:55:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 18 DD037 DD037-May07-11-50-11 2007-05-07 12:56:11.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:56:16.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-7 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:56:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:56:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:56:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:56:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 13 DD037 DD037-May07-11-50-11 2007-05-07 12:56:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 INCORRECT 1 "P=4*$p*r^2*i" Undefined variable: i 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:57:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 57 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD037 DD037-May07-11-50-11 2007-05-07 12:57:12.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD037 DD037-May07-11-50-11 2007-05-07 12:57:17.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 88 DD037 DD037-May07-11-57-40 2007-05-07 12:58:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD037 DD037-May07-11-57-40 2007-05-07 12:59:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 25 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD037 DD037-May07-11-57-40 2007-05-07 13:00:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD037 DD037-May07-11-57-40 2007-05-07 13:00:20.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 0 "P=I*a*.28" Undefined variable: a 1 GIVEN-FRACTION USNA SP212 General Physics II 23 DD037 DD037-May07-11-57-40 2007-05-07 13:00:24.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 0 "P=I*A*.28" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 GIVEN-FRACTION USNA SP212 General Physics II 49 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR) 0.28)) DD037 DD037-May07-11-57-40 2007-05-07 13:00:24.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=I*A*.28" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 49 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR) 0.28)) DD037 DD037-May07-11-57-40 2007-05-07 13:00:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 1 "A" USNA SP212 General Physics II DD037 DD037-May07-11-57-40 2007-05-07 13:00:35.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476191 m^2" USNA SP212 General Physics II 80 DD037 DD037-May07-12-00-50 2007-05-07 13:01:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD037 DD037-May07-12-00-50 2007-05-07 13:03:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:03:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:03:50.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT 0 "P=2*I*A" Units are inconsistent. 1 1 DRAW-BODY USNA SP212 General Physics II 12 (= Pr_SAIL (* (* 2 int_SAIL_SUNLIGHT_1) A_SAIL)) DD037 DD037-May07-12-00-50 2007-05-07 13:04:24.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 CORRECT System-4 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 24 DD037 DD037-May07-12-00-50 2007-05-07 13:04:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sail;forcetype=Thrust;time=T0;dir=0;mag=163 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 23 DD037 DD037-May07-12-00-50 2007-05-07 13:04:39.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A force arise from the interaction of two DIFFERENT objects, but you have used the sail for both. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:04:52.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Thrust;time=T0;dir=0;mag=163 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:04:53.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F There is indeed a force on the sail due to the sunlight, but it is not a thrust force. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:04:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-6 label=F It is a pressure force 2 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 18 DD037 DD037-May07-12-00-50 2007-05-07 13:05:05.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=163 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 17 DD037 DD037-May07-12-00-50 2007-05-07 13:05:12.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 INCORRECT Axes-6 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:05:15.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Axes-6 label=NIL Although it is always okay to draw a coordinate system, none are needed for this problem. Click on the light bulb button or 'explain further' for suggestions on how to solve the problem without drawing axes. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:05:21.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-5 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:05:35.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=163 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:05:46.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 11 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=163 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:05:54.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT 0 Units are inconsistent. 1 1 DEFINE-PRESSURE USNA SP212 General Physics II 12 DD037 DD037-May07-12-00-50 2007-05-07 13:09:10.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 INCORRECT 0 "P=1/A*I/C" Undefined variable: C 1 DEFINE-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:09:14.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 INCORRECT 0 "P=1/A*I/c" Units are inconsistent. 1 1 DEFINE-PRESSURE USNA SP212 General Physics II (= Pr_SAIL (/ (* (/ 1 A_SAIL) int_SAIL_SUNLIGHT_1) c)) DD037 DD037-May07-12-00-50 2007-05-07 13:09:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:09:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:09:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:10:40.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 8 INCORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="20 mN" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:10:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 9 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 12 DD037 DD037-May07-12-00-50 2007-05-07 13:11:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 20 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD037 DD037-May07-12-00-50 2007-05-07 13:11:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:11:14.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:11:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT radiation-pressure Good! the sunlight reflects off the sail. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:09.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 INCORRECT 1 "Fp=2*I/c" Undefined variable: Fp 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:14.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 INCORRECT 1 "F=2*I/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD037 DD037-May07-12-00-50 2007-05-07 13:12:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:36.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT 1 Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 15 DD037 DD037-May07-12-00-50 2007-05-07 13:12:42.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 INCORRECT 1 "F=2*(I/c)" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (* 2 (/ int_SAIL_SUNLIGHT_1 c))) DD037 DD037-May07-12-00-50 2007-05-07 13:12:45.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT 1 Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 10 DD037 DD037-May07-12-00-50 2007-05-07 13:12:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 11 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 12 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:12:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 13 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 5 DD037 DD037-May07-12-00-50 2007-05-07 13:13:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 14 CORRECT 1 "P=2*(I/c)" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 24 (= Pr_SAIL (* 2 (/ int_SAIL_SUNLIGHT_1 c))) DD037 DD037-May07-12-00-50 2007-05-07 13:13:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:13:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 41 DD037 DD037-May07-12-00-50 2007-05-07 13:13:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 INCORRECT 3 "A" Unable to solve for A. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:13:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 61 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DD037 DD037-May07-12-00-50 2007-05-07 13:13:45.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT 4 "P" USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:14:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 5 CORRECT 4 "A" USNA SP212 General Physics II DD037 DD037-May07-12-00-50 2007-05-07 13:14:18.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 72 DD193 DD193-May07-13-01-03 2007-05-07 14:02:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:02:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD193 DD193-May07-13-01-03 2007-05-07 14:02:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:04:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:04:46.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:06:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:06:10.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:07:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 HINT magnetic-dipole-energy No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:07:51.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 7 HINT (magnetic-dipole-moment ((?axis . z))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:07:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 8 HINT A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 5 DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:07:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 9 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 6 6 DEFINE-AMPLITUDE USNA SP212 General Physics II 20 DD193 DD193-May07-13-01-03 2007-05-07 14:08:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 10 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:08:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:09:16.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 INCORRECT 0 "vmax=B*" Syntax error in vmax=B* 1 USNA SP212 General Physics II 18 ? DD193 DD193-May07-13-01-03 2007-05-07 14:09:16.0 US/Eastern CALC_REQUEST Simplify CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 2 INCORRECT 1 "vmax=B*" Only correct equations may be simplified. 1 USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:09:32.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 INCORRECT 0 "vmax=B*$w" Undefined variables: (vmax $w) 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 17 DD193 DD193-May07-13-01-03 2007-05-07 14:09:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:09:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:09:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:09:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 12 DD193 DD193-May07-13-01-03 2007-05-07 14:10:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 56 (= ampE_WAVE (* c ampM_WAVE)) DD193 DD193-May07-13-01-03 2007-05-07 14:10:15.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 3 CORRECT 1 "B" USNA SP212 General Physics II DD193 DD193-May07-13-01-03 2007-05-07 14:10:24.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 88 DD193 DD193-May07-13-11-14 2007-05-07 14:11:54.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280k" Syntax error in P=280k 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II ? DD193 DD193-May07-13-11-14 2007-05-07 14:12:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 12 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD193 DD193-May07-13-11-14 2007-05-07 14:12:27.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-2 label="q";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 14 DD193 DD193-May07-13-11-14 2007-05-07 14:12:58.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Vector-3 label="d";type=Displacement;body=P;agent=NIL;time=T0;dir=0;mag=237 DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DD193 DD193-May07-13-11-14 2007-05-07 14:13:02.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Vector-3 label=d None of the solutions that I know include a displacement vector. Try clicking on the light bulb button or 'explain further' for suggestions about another approach. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:13:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:13:14.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 13 DD193 DD193-May07-13-11-14 2007-05-07 14:14:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:14:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:14:41.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 CORRECT Vector-7 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=242 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 14 DD193 DD193-May07-13-11-14 2007-05-07 14:14:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:15:03.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD193 DD193-May07-13-11-14 2007-05-07 14:15:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:15:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:16:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 CORRECT Var-8 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:07.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:14.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT electromagnetic-wave-field-amplitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT (magnetic-dipole-torque ((?axis . z))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 18 DD193 DD193-May07-13-11-14 2007-05-07 14:18:48.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-9 label="q2";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II 19 DD193 DD193-May07-13-11-14 2007-05-07 14:18:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:18:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:19:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:19:37.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 INCORRECT 1 "I=P/r" Units are inconsistent. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 18 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 r_P_TRANSMITTER_1)) DD193 DD193-May07-13-11-14 2007-05-07 14:20:42.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 INCORRECT 1 "I=P/$pr^2" Undefined variable: $pr 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:20:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 INCORRECT 1 "I=P/$p*r^2" Units are inconsistent. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 17 (= int_P_TRANSMITTER_1 (* (/ power_TRANSMITTER_1 $P) (^ r_P_TRANSMITTER_1 2))) DD193 DD193-May07-13-11-14 2007-05-07 14:21:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 7 INCORRECT 1 "I=P/($p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* $P (^ r_P_TRANSMITTER_1 2)))) DD193 DD193-May07-13-11-14 2007-05-07 14:21:10.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 8 HINT 1 What equation do you wish to write? 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:21:15.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 9 HINT (magnetic-dipole-moment ((?axis . z))) I'm afraid that the equation type that you selected does not appear in any of the solutions to this problem. Why don't you try something different or go to Light-Bulb-Help if you do not know what to do. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 12 DD193 DD193-May07-13-11-14 2007-05-07 14:21:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 10 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:21:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 11 HINT If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:21:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 12 HINT Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:21:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 13 HINT Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 7 DD193 DD193-May07-13-11-14 2007-05-07 14:22:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 14 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 51 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD193 DD193-May07-13-11-14 2007-05-07 14:22:50.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD193 DD193-May07-13-11-14 2007-05-07 14:22:59.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 82 DD193 DD193-May07-13-24-14 2007-05-07 14:25:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="Pe";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:25:17.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=Pe I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:25:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:25:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 3 3 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD193 DD193-May07-13-24-14 2007-05-07 14:25:45.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DD193 DD193-May07-13-24-14 2007-05-07 14:26:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:26:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT Var-3 label="Is";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960Wm^2" Syntax error in Is=960Wm^2 1 DEFINE-INTENSITY USNA SP212 General Physics II -3 ? DD193 DD193-May07-13-24-14 2007-05-07 14:27:06.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-3 label="Is";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960Wm^2" Syntax error in Is=960Wm^2 1 DEFINE-INTENSITY USNA SP212 General Physics II ? DD193 DD193-May07-13-24-14 2007-05-07 14:27:20.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 INCORRECT Var-3 label="Is";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W*m^2" Units are inconsistent. 1 1 DEFINE-INTENSITY USNA SP212 General Physics II -4 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W*m^2)) DD193 DD193-May07-13-24-14 2007-05-07 14:27:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="Is";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 6 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD193 DD193-May07-13-24-14 2007-05-07 14:28:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:28:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:28:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 CORRECT Var-1 label="Pe";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DD193 DD193-May07-13-24-14 2007-05-07 14:28:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:06.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 5 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 6 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:39.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 7 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 8 HINT radiation-pressure No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:56.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 9 HINT (polarizer-intensity ((?fraction . 1))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:29:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 10 HINT A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-4 label="Ps";quant=power;subtype=NIL;body=sunlight;agent=collector;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-4 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 17 DD193 DD193-May07-13-24-14 2007-05-07 14:30:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT You should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:30:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:31:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 INCORRECT Var-6 label="P";quant=power;subtype=NIL;body=collector;agent=all forces;time=T0;value="" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:31:47.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Var-6 label=P Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:31:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 HINT Click on the light bulb button or 'explain further' for suggestions on how to solve this problem. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:31:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 6 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:31:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 7 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:32:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 8 HINT The power going through a surface is just the intensity times the area of the surface. 5 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:32:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 9 HINT Write the equation Ps = A * Is 6 6 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 12 DD193 DD193-May07-13-24-14 2007-05-07 14:32:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 10 CORRECT 0 "Ps=A*Is" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 56 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD193 DD193-May07-13-24-14 2007-05-07 14:32:23.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 INCORRECT 1 "A" Unable to solve for A. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:32:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:32:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:32:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation Pe = 0.28 * Ps 3 3 GIVEN-FRACTION USNA SP212 General Physics II 51 DD193 DD193-May07-13-24-14 2007-05-07 14:33:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 INCORRECT 1 "Pe=,28*Ps" GIVEN-FRACTION USNA SP212 General Physics II 50 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 28 power_COLLECTOR_SUNLIGHT_1)) DD193 DD193-May07-13-24-14 2007-05-07 14:33:15.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 5 HINT 1 What equation do you wish to write? 1 GIVEN-FRACTION USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:33:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 6 CORRECT 1 "Pe=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II 51 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD193 DD193-May07-13-24-14 2007-05-07 14:33:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DD193 DD193-May07-13-24-14 2007-05-07 14:33:38.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 82 DD193 DD193-May07-13-34-23 2007-05-07 14:34:47.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD193 DD193-May07-13-34-23 2007-05-07 14:35:18.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-3 label="de";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II 3 DD193 DD193-May07-13-34-23 2007-05-07 14:35:29.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT System-3 label=de What other bodies can you define? 1 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:35:39.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-3 label="dm";body=(earth moon);time=NIL DRAW-BODY USNA SP212 General Physics II 2 DD193 DD193-May07-13-34-23 2007-05-07 14:35:45.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 HINT System-3 label=dm What other bodies can you define? 1 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:35:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 HINT Analyzing the pulse is more important for solving this problem. 2 DRAW-BODY USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:36:04.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 6 CORRECT System-3 label="dp";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 3 DD193 DD193-May07-13-34-23 2007-05-07 14:36:57.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:37:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 12 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD193 DD193-May07-13-34-23 2007-05-07 14:37:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T0 to T1. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:38:13.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:38:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 22 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD193 DD193-May07-13-34-23 2007-05-07 14:38:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-6 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:39:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 INCORRECT 0 "s2=s*s1" Units are inconsistent. 1 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (* dist_PULSE_23 dist_PULSE_12)) DD193 DD193-May07-13-34-23 2007-05-07 14:39:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 CORRECT 0 "s2=s+s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_23 dist_PULSE_12)) DD193 DD193-May07-13-34-23 2007-05-07 14:39:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:39:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:40:13.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "v" |average| |speed| |pulse| |T0 to T2| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:40:24.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT #.(wb-quant '(define-variable "v" |instantaneous| |speed| |pulse| |T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:40:26.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT #.(wb-quant '(define-variable "n" |NIL| |index-of-refraction| |space| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the duration of the interval from T0 to T2. 4 4 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:40:33.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:07.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:14.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 7 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 9 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 8 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 10 HINT Your goal should be introducing a variable for the speed of the pulse. 9 DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 11 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 10 10 DEFINE-SPEED USNA SP212 General Physics II 17 DD193 DD193-May07-13-34-23 2007-05-07 14:41:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 12 CORRECT Var-7 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:41:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:42.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 INCORRECT 1 "s2=v*T" Undefined variable: T 1 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 6 HINT A good step would be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:42:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 7 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II 12 DD193 DD193-May07-13-34-23 2007-05-07 14:43:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 8 CORRECT Var-8 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:43:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "s2=v*t" WRITE-SDD USNA SP212 General Physics II 56 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DD193 DD193-May07-13-34-23 2007-05-07 14:44:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:44:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 2 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD193 DD193-May07-13-34-23 2007-05-07 14:44:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "s2" USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:44:32.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 4 "t" USNA SP212 General Physics II DD193 DD193-May07-13-34-23 2007-05-07 14:44:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 88 DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:23.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Answer-1 "120V" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:30.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 INCORRECT Answer-1 "120 V/m" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 5 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:41:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 6 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 4 4 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 7 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 20 (= ampE_WAVE (DNUM 120 V/m)) DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:24.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 15 DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 59 (= ampE_WAVE (* c ampM_WAVE)) DD1AB DD1AB-May03-09-41-05 2007-05-03 10:42:54.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD1AB DD1AB-May03-09-41-05 2007-05-03 10:43:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 86 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:43:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:43:44.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:43:48.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 4 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:26.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 HINT Var-3 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 5 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 6 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:44:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 7 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -1 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 8 CORRECT Var-4 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 9 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:20.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-5 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=239 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 19 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:46.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:56.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:45:57.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT A good step would be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 14 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-6 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 9 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:33.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 4 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:46.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-8 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:46:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -1 DD1AB DD1AB-May03-09-43-28 2007-05-03 10:47:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 43 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD1AB DD1AB-May03-09-43-28 2007-05-03 10:47:36.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD1AB DD1AB-May03-09-43-28 2007-05-03 10:47:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 74 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:48:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 25 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:13.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:22.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT System-4 label="c";body=collector;time=NIL DEFINE-POWER-VAR USNA SP212 General Physics II 23 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:25.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT System-4 label=c This problem doesn't require a body to be drawn. For suggestions about how to solve it, click on the light bulb button or 'explain further'. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:49:55.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:07.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:08.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 18 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 CORRECT Var-5 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 19 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT A good step would be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 14 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:50:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Ps = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 9 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Ps=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 53 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Ps 3 3 GIVEN-FRACTION USNA SP212 General Physics II 48 DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:38.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD1AB DD1AB-May03-09-48-01 2007-05-03 10:51:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 79 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sunlight;agent=sail;time=T0;value="1.3 kW/m^2" DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:32.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT Var-1 label=I I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 2 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 HINT You should use the body tool to draw a body choosing the sail as the body. 3 3 DRAW-BODY USNA SP212 General Physics II -5 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:46.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 5 CORRECT System-2 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 9 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 3 HINT Try introducing a variable for the intensity supplied to the sail at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:52:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the sail at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II 4 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:53:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 13 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD1AB DD1AB-May03-09-51-58 2007-05-03 10:54:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:54:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DEFINE-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:54:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 14 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:54:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:54:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F You should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 9 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:55:55.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=61 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 18 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:33.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:37.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT harmonic-of No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 13 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 32 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD1AB DD1AB-May03-09-51-58 2007-05-03 10:56:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:04.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 " 8.672666475151953e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 49 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 44 DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 63 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:21.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DD1AB DD1AB-May03-09-51-58 2007-05-03 10:57:28.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 74 DD1AB DD1AB-May03-09-57-39 2007-05-03 10:58:14.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 10:58:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 10:58:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DD1AB DD1AB-May03-09-57-39 2007-05-03 10:58:27.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 CORRECT System-2 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -2 DD1AB DD1AB-May03-09-57-39 2007-05-03 10:58:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 9 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 CORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 18 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 19 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:33.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 10:59:55.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:01.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:07.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT A good step would be introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II 14 DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-6 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II 9 DD1AB DD1AB-May03-09-57-39 2007-05-03 11:00:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-7 label="stot";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 1 "stot=2*s1" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 1 "stot=2*s1" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 1 "stot=2*s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT You should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II 4 DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:51.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-8 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:01:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and stot is the distance travelled, and t is the duration of the trip, write v=stot/t. 6 6 WRITE-SDD USNA SP212 General Physics II -1 DD1AB DD1AB-May03-09-57-39 2007-05-03 11:02:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 2 "v=stot/t" WRITE-SDD USNA SP212 General Physics II 43 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DD1AB DD1AB-May03-09-57-39 2007-05-03 11:02:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 38 DD1AB DD1AB-May03-09-57-39 2007-05-03 11:02:18.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "t" USNA SP212 General Physics II DD1AB DD1AB-May03-09-57-39 2007-05-03 11:02:25.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 " 2.5617722511218077 s" USNA SP212 General Physics II 69 DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:49:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 INCORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" The value of B is not given in this problem. It should be marked unknown. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:50:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 3 DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:50:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-3 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 (= ampE_WAVE (DNUM 120 V/m)) DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:51:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:51:20.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:52:22.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:52:31.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT period-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:53:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:53:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 18 DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:53:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 62 (= ampE_WAVE (* c ampM_WAVE)) DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:53:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-49-18 2007-04-12 19:53:32.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:55:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:55:57.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-1 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:56:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:56:55.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:57:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:57:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:58:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 INCORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=P;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 2 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:58:25.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 HINT Var-3 label=P Are you sure you want to choose P? 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:58:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 5 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 12 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:58:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:58:57.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=236 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 13 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 19:59:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:15.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |transmitter| |T0| |all sources| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 5 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:00:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 6 DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:01:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:02:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:02:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:02:50.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:04:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:05:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:05:18.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II 24 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:05:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:05:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:05:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:06:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 19 DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:06:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 INCORRECT 1 "P=4*$p^(r^2)*I" Units are inconsistent. 1 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 18 (= power_TRANSMITTER_1 (* (* 4 (^ $P (^ r_P_TRANSMITTER_1 2))) int_P_TRANSMITTER_1)) DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:07:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:10:35.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:10:44.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-18-55-23 2007-04-12 20:10:56.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 " 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 93 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:51:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=all forces;time=T0;value="2.0 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:51:03.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:51:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:52:24.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:52:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:52:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:52:51.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 2 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:53:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:54:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:54:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:54:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 8 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:55:16.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 7 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:55:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 17 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:58:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:58:19.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |sunlight| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:58:25.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:59:11.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:59:13.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 5 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:59:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 6 DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 20:59:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-5 label="Pc";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:01:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:02:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT You should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:02:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 12 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:02:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 13 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:03:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:04:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:04:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:04:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Pc = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 8 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:04:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Pc=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 52 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:13:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:14:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:14:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Pc 3 3 GIVEN-FRACTION USNA SP212 General Physics II 47 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:14:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Pc" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:15:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 42 DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:15:44.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-19-48-42 2007-04-12 21:15:51.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 73 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:32:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:33:05.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 CORRECT System-1 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 17 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:33:11.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 INCORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:33:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:33:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 3 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:33:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 13 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:34:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 22 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:35:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:37:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 23 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:38:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:38:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Your goal should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:38:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:38:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:38:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 18 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:39:37.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=107 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:42:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:42:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:42:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:45:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 27 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:45:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:45:31.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:45:49.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT radiation-pressure Very good. the sunlight reflects off the sail. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:12.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 INCORRECT 1 "F=2*I/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 26 (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:20.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 INCORRECT 1 "F=2*I/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:46:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:47:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 45 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:48:57.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 62 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT Try introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 HINT Define a variable for the area of the sail by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 57 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 5 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 52 DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:49:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 72 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:50:03.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DD2A7 DD2A7-Apr12-20-29-48 2007-04-12 21:50:10.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 83 DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:37:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:37:34.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 6 DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:37:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:37:44.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:39:00.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Vector-3 label="d";type=Displacement;body=pulse;agent=NIL;time=T0 to T1;dir=0;mag=257 DEFINE-DISTANCE USNA SP212 General Physics II 4 DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:39:04.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT Vector-3 label=d On this problem, you need to use distance rather than displacement. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:39:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-4 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 14 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:40:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:41:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-5 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 24 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:41:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:41:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "NIL" |NIL| |length| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:41:47.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:42:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:42:15.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT speed-equals-wave-speed That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 5 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:42:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 6 DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:42:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 CORRECT Var-6 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:43:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:43:45.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "(s+s2)=v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 49 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:43:45.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "(s+s2)=v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 49 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:43:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:44:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:44:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DD2A7 DD2A7-Apr16-18-36-45 2007-04-16 19:44:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 81 DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:34:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:34:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:34:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:34:49.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:35:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:35:22.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:35:26.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:35.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 7 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:40.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 8 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 9 HINT electromagnetic-wave-field-amplitude Right. A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 10 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 5 5 DEFINE-AMPLITUDE USNA SP212 General Physics II 20 DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 11 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:36:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Why don't you continue with the solution by working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:37:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:37:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 15 DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:37:12.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 59 (= ampE_WAVE (* c ampM_WAVE)) DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:37:25.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-32-56 2007-04-29 21:37:34.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 90 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:40:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:40:43.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:41:01.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-1 label="moon";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:41:13.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 CORRECT System-1 label="pulse";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 2 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:41:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:41:27.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:41:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:42:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:42:18.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:42:31.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT Var-3 label=s The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II -2 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:42:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 8 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:46:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:46:48.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s12 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 7 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:47:06.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 INCORRECT Var-4 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8" Forgot to put units on a number. 1 DEFINE-DISTANCE USNA SP212 General Physics II (= dist_PULSE_23 3.84e+8) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:47:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 CORRECT Var-4 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 17 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:47:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-DURATION USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:47:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-5 label="t02";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:47:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:03.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:32.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:46.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 4 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 6 HINT Try introducing a variable for the speed of the pulse. 6 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:48:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 7 CORRECT Var-6 label="v";quant=wave-speed;subtype=NIL;body=space;agent=NIL;time=NIL;value="" DEFINE-WAVE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT A good step would be introducing a variable for the speed of the pulse. 3 DEFINE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 CORRECT Var-7 label="vp";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:49:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 CORRECT Var-8 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 18 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s2=s+s12" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:50:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because vp is the speed of the pulse from T0 to T2, and s2 is the distance travelled, and t02 is the duration of the trip, write vp=s2/t02. 6 6 WRITE-SDD USNA SP212 General Physics II 13 DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:51:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 1 "vp=s2/t02" WRITE-SDD USNA SP212 General Physics II 57 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:52:04.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 INCORRECT 2 "t02" Unable to solve for t02. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:52:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:52:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 2 "vp=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:52:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "t02" USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-38-03 2007-04-29 21:52:38.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 88 DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:56:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:57:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:57:23.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:57:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:58:21.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-5 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=117 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:58:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:58:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:58:41.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT doppler-frequency No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:18.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 20 DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-6 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 15 DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:49.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 21:59:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 10 DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:05.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-8 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 5 DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 49 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:00:57.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD2BF DD2BF-Apr29-20-53-19 2007-04-29 22:01:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 80 DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:08:58.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2.0 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:09:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:09:13.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:09:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:09:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:09:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:10:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:10:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 23 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:10:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:10:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:12:07.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:12:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-5 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 24 DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:12:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:13:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "Ps=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 68 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:13:32.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "Ps=.28P" Syntax error in Ps=.28P 1 GIVEN-FRACTION USNA SP212 General Physics II 67 ? DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:13:38.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 1 "Ps=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:13:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 INCORRECT 1 "Ps=.72*P" GIVEN-FRACTION USNA SP212 General Physics II 66 (= power_COLLECTOR_SUNLIGHT_1 (* 0.72 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:15:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:15:36.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-01-32 2007-04-29 22:15:44.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 98 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:21:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:26:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:26:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:26:26.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-2 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:26:32.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DEFINE-PRESSURE USNA SP212 General Physics II 18 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:26:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:27:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 19 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:27:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:28:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:28:47.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=74 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 18 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:28:50.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:03.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=74 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 27 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:51.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |sail| |T0| |sunlight| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:55.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |sail| |T0| |all sources| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:29:58.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT #.(wb-quant '(define-variable "NIL" |NIL| |length| |sail| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the pressure at the sail at T0. 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:03.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT (nsl ((?axis . y))) No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:29.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT (ntl-vector ((?axis . x))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT the sunlight reflects off the sail. 8 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 9 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 HINT Write the equation P = (2 * I) / c 10 10 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 22 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 11 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 41 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:30:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT You should be introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 42 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 37 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 56 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:31:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 3 "P" USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:32:03.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 73 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:32:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 68 DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:32:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT 4 "A" USNA SP212 General Physics II DD2BF DD2BF-Apr29-21-17-51 2007-04-29 22:32:21.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 79 DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:31:59.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:32:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:32:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:32:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= (/ ampE_WAVE ampM_WAVE) c) DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:32:26.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-30-03 2007-04-05 11:32:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 98 DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:35:50.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=238 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 6 DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:35:53.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:36:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:36:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:36:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:36:33.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A 1 1 INCORRECT 1 "P=I/c" Units are inconsistent. 1 1 USNA SP212 General Physics II 24 (= power_TRANSMITTER_1 (/ int_P_TRANSMITTER_1 c)) DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:36:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A 1 2 INCORRECT 1 "P=2*(I/c)" Units are inconsistent. 1 1 USNA SP212 General Physics II 23 (= power_TRANSMITTER_1 (* 2 (/ int_P_TRANSMITTER_1 c))) DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:37:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A Unknown 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:38:31.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A 1 3 INCORRECT 1 "P=(I*2)/c" Units are inconsistent. 1 1 USNA SP212 General Physics II 22 (= power_TRANSMITTER_1 (/ (* int_P_TRANSMITTER_1 2) c)) DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:41:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Var-7 1 INCORRECT Var-7 label="$w";quant=angular-frequency;subtype=NIL;body=transmitter;agent=NIL;time=NIL;value="" USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-35-04 2007-04-05 11:41:16.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A 1 4 HINT 1 Units are inconsistent. 1 1 USNA SP212 General Physics II 17 DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:42:55.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:43:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 12 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:43:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 23 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:43:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:43:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 ".28*(A*I)=P" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 GIVEN-FRACTION USNA SP212 General Physics II 49 (= (* 0.28 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) power_ELECTRIC_OUTPUT_COLLECTOR_1) DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:43:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 ".28*(A*I)=P" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 49 (= (* 0.28 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) power_ELECTRIC_OUTPUT_COLLECTOR_1) DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:44:02.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 1 "A" USNA SP212 General Physics II DD2DD DD2DD-Apr05-10-42-31 2007-04-05 11:44:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 " 7440.476190476191 m^2" USNA SP212 General Physics II 80 DD2DD DD2DD-Apr05-10-51-43 2007-04-05 11:51:50.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A 1 5 INCORRECT 1 "P=(I)/c" Units are inconsistent. 1 1 USNA SP212 General Physics II (= power_TRANSMITTER_1 (/ int_P_TRANSMITTER_1 c)) DD2DD DD2DD-Apr05-10-51-43 2007-04-05 11:51:54.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A 1 6 INCORRECT 1 "P=(2*I)/c" Units are inconsistent. 1 1 USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (/ (* 2 int_P_TRANSMITTER_1) c)) DD2DD DD2DD-May07-16-22-38 2007-05-07 17:22:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD457 DD457-Apr01-17-49-59 2007-04-01 18:50:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD457 DD457-Apr01-17-49-59 2007-04-01 18:50:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:51:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:51:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:52:01.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:52:52.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT lr-time-constant No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 59 DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 2 CORRECT 1 "B" USNA SP212 General Physics II DD457 DD457-Apr01-17-49-59 2007-04-01 18:56:55.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 90 DD457 DD457-Apr01-17-57-11 2007-04-01 18:57:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:58:02.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD457 DD457-Apr01-17-57-11 2007-04-01 18:58:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:58:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:58:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 11 DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=266 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:39.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 CORRECT 0 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 20 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 18:59:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:01:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:01:58.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT You should be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II 15 DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:02:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 10 DD457 DD457-Apr01-17-57-11 2007-04-01 19:03:33.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-5 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:03:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:03:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:03:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 5 DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:09.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 44 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 39 DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DD457 DD457-Apr01-17-57-11 2007-04-01 19:04:59.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 70 DD457 DD457-Apr12-10-19-21 2007-04-12 11:20:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:20:12.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD457 DD457-Apr12-10-19-21 2007-04-12 11:20:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DD457 DD457-Apr12-10-19-21 2007-04-12 11:21:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 M/m^2" Syntax error in I=960 M/m^2 1 DEFINE-INTENSITY USNA SP212 General Physics II 14 ? DD457 DD457-Apr12-10-19-21 2007-04-12 11:21:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT The equation or the units in it are not in a recognizable form. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:21:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 23 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD457 DD457-Apr12-10-19-21 2007-04-12 11:22:06.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:22:17.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:26:32.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:26:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II 18 DD457 DD457-Apr12-10-19-21 2007-04-12 11:26:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-4 label="Pc";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 19 DD457 DD457-Apr12-10-19-21 2007-04-12 11:26:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:26:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT You should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:27:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 14 DD457 DD457-Apr12-10-19-21 2007-04-12 11:27:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:27:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Pc = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 9 DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Pc=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 53 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * Pc 3 3 GIVEN-FRACTION USNA SP212 General Physics II 48 DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*Pc" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 43 DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DD457 DD457-Apr12-10-19-21 2007-04-12 11:28:51.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 " 7440.476190476189 m^2" USNA SP212 General Physics II 74 DD457 DD457-Apr12-10-29-02 2007-04-12 11:30:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD457 DD457-Apr12-10-29-02 2007-04-12 11:30:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:30:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DD457 DD457-Apr12-10-29-02 2007-04-12 11:30:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-2 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DD457 DD457-Apr12-10-29-02 2007-04-12 11:30:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DEFINE-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 CORRECT Var-3 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:31:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 15 DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:13.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=112 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-5 label=F You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-5 label=F The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:30.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=112 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:39.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 INCORRECT 0 "F= 20 nM" Syntax error in F= 20 nM 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 ? DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 INCORRECT 0 "F= 20 nN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 13 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 nN)) DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:48.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 INCORRECT 0 "F= 20 nM" Syntax error in F= 20 nM 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II ? DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT The equation or the units in it are not in a recognizable form. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:32:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 HINT Though I can't tell exactly what the mistake is, a few common sources of errors are: (a) Unit symbols are case sensitive. (b) Multiplication always requires an explicit multiplication sign: W=m*g, NOT W=mg. (c) Units attach only to numbers, not to variables or expressions. 3 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:33:01.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 6 INCORRECT 0 "F=20 nM" Syntax error in F=20 nM 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II ? DD457 DD457-Apr12-10-29-02 2007-04-12 11:33:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 7 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 21 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD457 DD457-Apr12-10-29-02 2007-04-12 11:35:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:35:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:35:58.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT radiation-pressure That's right. the sunlight reflects off the sail. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT Write the equation P = (2 * I) / c 5 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 16 DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 36 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT Your goal should be introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:36:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 31 DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 51 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 46 DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 3 "P" USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:43.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:51.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 62 DD457 DD457-Apr12-10-29-02 2007-04-12 11:41:59.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 73 DD45D DD45D-Apr21-21-26-40 2007-04-21 22:27:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD45D DD45D-Apr21-21-26-40 2007-04-21 22:27:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:27:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:27:41.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:06.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:20.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD45D DD45D-Apr21-21-26-40 2007-04-21 22:28:29.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027e-7 T" USNA SP212 General Physics II 95 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:27.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:34.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:30:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -4 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:31:36.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 5 INCORRECT Vector-4 label="d";type=Displacement;body=pulse;agent=NIL;time=T0 to T1;dir=0;mag=93 DEFINE-DISTANCE USNA SP212 General Physics II -6 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:31:41.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT Vector-4 label=d On this problem, you need to use distance rather than displacement. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:31:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT Define a variable for the distance travelled by the pulse from T0 to T1. 2 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -11 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:01.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 6 INCORRECT Var-5 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -12 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 7 INCORRECT Var-5 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.48e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_12 (DNUM 3.48e+8 m)) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:22.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 8 HINT Var-5 label=s 3.48e+8 m is not the correct value for s. Reread the problem statement carefully to find the given value for s, the distance travelled by the pulse from T0 to T1. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 9 HINT The correct value for s is 384000000 m. 2 2 DEFINE-DISTANCE USNA SP212 General Physics II -17 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 10 CORRECT Var-5 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -8 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:32:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -12 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 CORRECT Var-6 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -3 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:27.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 2 HINT #.(wb-quant '(define-variable "v" |instantaneous| |velocity| |pulse| |T1| |NIL| NIL "") 'xc) That quantity is not mentioned in the Andes solution. 2 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 3 HINT #.(wb-quant '(define-variable "$w" |NIL| |angular-frequency| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 4 HINT #.(wb-quant '(define-variable "g" |NIL| |gravitational-acceleration| |pulse| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the duration of the interval from T0 to T2. 4 4 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:31.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:35.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 6 HINT point-charge-efield-mag No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 7 HINT (net-field-electric ((?axis . x))) No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 7 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 8 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 8 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 9 HINT Try introducing a variable for the speed of the pulse. 9 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:33:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 10 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 10 10 DEFINE-SPEED USNA SP212 General Physics II -8 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 11 INCORRECT Var-7 label="v";quant=speed;subtype=instantaneous;body=pulse;agent=NIL;time=T0;value="3.0e8 m/s" DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:06.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 12 HINT Var-7 label=v To define the speed of waves moving in the space, use "Speed of wave" instead of "speed." 1 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II -13 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:25.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 13 INCORRECT Var-8 label="v";quant=wave-speed;subtype=NIL;body=space;agent=NIL;time=NIL;value="3.0e8 m/s" The value of v is not given in this problem. It should be marked unknown. 1 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:30.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 14 HINT Var-8 label=v The value of v is not given in this problem. It should be marked unknown. 1 1 DEFINE-WAVE-SPEED USNA SP212 General Physics II -18 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (WAVE-SPEED SPACE)) 15 CORRECT Var-8 label="v";quant=wave-speed;subtype=NIL;body=space;agent=NIL;time=NIL;value="" DEFINE-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE c)) 1 CORRECT 0 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= wv_SPACE c) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT You should be introducing a variable for the speed of the pulse. 3 DEFINE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:34:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 4 4 DEFINE-SPEED USNA SP212 General Physics II -23 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 CORRECT Var-9 label="vp";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT You should be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -28 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-10 label="sp";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II -27 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Your goal should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II -32 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-11 label="t2";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:35:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because vp is the speed of the pulse from T0 to T2, and sp is the distance travelled, and t2 is the duration of the trip, write vp=sp/t2. 6 6 WRITE-SDD USNA SP212 General Physics II -37 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:07.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 1 "vp=sp/t2" WRITE-SDD USNA SP212 General Physics II 7 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 1 HINT Why don't you continue with the solution by working on noting the speed of the pulse is the same as the wave speed of the space. 1 SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 2 HINT The velocity of any wave in space or on a given string, rope, et cetera is the same. 2 SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 3 HINT If there are two waves moving through the same medium then they have equal speeds. 3 SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 4 HINT Write the equation v = vp 4 4 SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II 2 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 5 CORRECT 2 "v=vp" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= wv_SPACE sp_PULSE_13) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II -3 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:33.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 INCORRECT 3 "?T02-VAR=s+s1" Syntax error in T02-VAR=s+s1 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II ? DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 HINT The equation or the units in it are not in a recognizable form. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 7 HINT Though I can't tell exactly what the mistake is, a few common sources of errors are: (a) Unit symbols are case sensitive. (b) Multiplication always requires an explicit multiplication sign: W=m*g, NOT W=mg. (c) Units attach only to numbers, not to variables or expressions. 3 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 8 HINT Why don't you continue working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 9 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 10 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:36:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 11 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II -8 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:37:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 12 CORRECT 3 "sp=s1+s" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_23 dist_PULSE_12)) DD45D DD45D-Apr21-21-29-56 2007-04-21 22:37:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II -13 DD45D DD45D-Apr21-21-29-56 2007-04-21 22:37:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 4 "t2" USNA SP212 General Physics II DD45D DD45D-Apr21-21-29-56 2007-04-21 22:37:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.56 s" USNA SP212 General Physics II 18 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:18.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 3 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 4 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -7 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:41.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -8 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 2 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:46:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II -3 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:36.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-4 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=251 DRAW-RELATIVE-POSITION USNA SP212 General Physics II -2 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:47:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:09.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:13.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "NIL" |NIL| |length| |P| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:17.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |P| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT #.(wb-quant '(define-variable "v" |instantaneous| |speed| |P| |T0| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:31.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT #.(wb-quant '(define-variable "f" |NIL| |frequency| |transmitter| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:34.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 HINT #.(wb-quant '(define-variable "Ft" |NIL| |string-tension| |P| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the intensity supplied to P at T0 due to the transmitter. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:35.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 8 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:39.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 9 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 10 HINT speed-equals-wave-speed No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 7 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 11 HINT You should be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 8 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:48:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 12 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 9 9 DEFINE-INTENSITY USNA SP212 General Physics II -2 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 13 CORRECT Var-5 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -7 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:44.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -12 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:54.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-8 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II -11 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:49:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -16 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:50:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 28 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD45D DD45D-Apr21-21-38-19 2007-04-21 22:50:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 23 DD45D DD45D-Apr21-21-38-19 2007-04-21 22:50:29.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DD45D DD45D-Apr21-21-38-19 2007-04-21 22:50:46.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815e-4 W/m^2" USNA SP212 General Physics II 54 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:31.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:51:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -4 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 6 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 1 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 10 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:52:59.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "$b" |NIL| |db-intensity| |electric_output| |T0| |collector| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:03.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "P" |NIL| |power| |electric_output| |T0| |collector| NIL "") 'NIL) That quantity is not sought by the problem statement. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:05.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT #.(wb-quant '(define-variable "NIL" |NIL| |length| |electric_output| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the area of the collector. 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:06.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:09.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 7 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:09.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT speed-equals-wave-speed No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT You should be introducing a variable for the power supplied to the collector from the sunlight at T0. 8 DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 9 9 DEFINE-POWER-VAR USNA SP212 General Physics II 5 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 10 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT You should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:53:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -5 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:01.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 39 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 34 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=0.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 29 DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:23.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DD45D DD45D-Apr21-21-51-20 2007-04-21 22:54:33.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.47 m^2" USNA SP212 General Physics II 60 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:35.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-1 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 3 HINT Try introducing a variable for the intensity supplied to the sail at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 4 HINT Define a variable for the intensity supplied to the sail at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II 7 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:55:49.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 13 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 8 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:18.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 INCORRECT Vector-3 label="p";type=Momentum;body=sail;agent=NIL;time=T0;dir=NIL;mag=114 DEFINE-PRESSURE USNA SP212 General Physics II 7 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:21.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 HINT Vector-3 label=p None of the solutions that I know include a momentum vector. Try clicking on the light bulb button or 'explain further' for suggestions about another approach. 1 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 8 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 9 HINT Your goal should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 3 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 10 HINT A force is exerted on the sail by the sunlight 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 11 HINT When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 12 HINT Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 6 6 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 2 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 13 INCORRECT Vector-3 label="p";type=Momentum;body=sunlight;agent=NIL;time=T0;dir=NIL;mag=114 DEFINE-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:56:45.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 14 INCORRECT Vector-3 label="p";type=Momentum;body=sunlight;agent=NIL;time=T0;dir=NIL;mag=114 DEFINE-PRESSURE USNA SP212 General Physics II 1 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 15 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 2 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F You should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II -3 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:27.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=Unspecified;forcetype=Pressure;time=T0;dir=NIL;mag=85 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:30.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT Vector-5 label=F Is the force is due to an unspecified agent? 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-6 label=F Forces are caused by interacting objects. The force can either be a field force, such as weight, in which case the objects do not have to touch. Or the force is a contact force, such as tension or friction, in which case the objects must touch. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-6 label=F Draw a pressure force on the sail at T0, but make it be due to the sunlight instead of an unspecified agent. 3 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II -8 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:36.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=85 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -13 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -4 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "$l" |NIL| |wavelength| |sail| |NIL| |sail| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:58.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT #.(wb-quant '(define-variable "$l" |NIL| |wavelength| |sail| |NIL| |sail| NIL "") 'NIL) In order to move ahead, you have to try selecting something that you haven't tried before. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:57:59.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT #.(wb-quant '(define-variable "T" |NIL| |period| |sail| |NIL| |NIL| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:01.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |sail| |T0| |sail| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the pressure at the sail at T0. 5 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:02.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT "OK" What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:05.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:06.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT harmonic-of No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 8 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT the sunlight reflects off the sail. 9 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 10 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 11 HINT Write the equation P = (2 * I) / c 11 11 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II -9 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 12 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 10 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT A good step would be introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:58:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT Define a variable for the area of the sail by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 5 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 20 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 15 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:15.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 3 "P" USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:25.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.67e-6 Pa" USNA SP212 General Physics II 32 DD45D DD45D-Apr21-21-54-45 2007-04-21 22:59:38.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095 m^2" USNA SP212 General Physics II 43 DD517 DD517-Apr10-15-02-18 2007-04-10 16:11:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD517 DD517-Apr10-15-02-18 2007-04-10 16:11:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:12:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:12:58.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:06.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT energy-decay No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:32.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DD517 DD517-Apr10-15-02-18 2007-04-10 16:13:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD517 DD517-Apr10-15-02-18 2007-04-10 16:14:07.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 8 CORRECT Answer-1 "4.0027691423778244e-7 T" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 95 DD517 DD517-Apr10-15-02-18 2007-04-10 16:14:14.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 9 INCORRECT 2 "c" Syntax error in c 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 93 ? DD517 DD517-Apr10-15-02-18 2007-04-10 16:14:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 10 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II (= ampE_WAVE (* c ampM_WAVE)) DD517 DD517-Apr10-15-02-18 2007-04-10 16:14:28.0 US/Eastern CALC_REQUEST Simplify CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 2 CORRECT 2 "E=c*B" USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:16:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84E8m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:17:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-3 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:17:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 1 CORRECT Var-4 label="ta";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T1;value="" DEFINE-DURATION USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 11 DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:20.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-5 label="P";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:32.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-6 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:18:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:19:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 CORRECT Var-7 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84E8m" DEFINE-DISTANCE USNA SP212 General Physics II 15 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:19:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:19:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T1| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:19:37.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:19:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 4 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:20:13.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 5 HINT speed-equals-wave-speed That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 5 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:20:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 6 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 6 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:20:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 7 HINT A good step would be introducing a variable for the speed of the pulse. 7 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:20:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 8 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 8 8 DEFINE-SPEED USNA SP212 General Physics II 10 DD517 DD517-Apr10-15-14-59 2007-04-10 16:20:37.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 9 CORRECT 0 "s" USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:21:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 2))) 1 CORRECT Var-8 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T1;value="" DEFINE-SPEED USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:21:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 2 3))) 1 CORRECT Var-9 label="v1";quant=speed;subtype=average;body=pulse;agent=NIL;time=T1 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:21:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 0 "s=v*ta" WRITE-SDD USNA SP212 General Physics II 31 (= dist_PULSE_12 (* sp_PULSE_12 t_12)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:22:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 2 3))) 1 CORRECT Var-10 label="tb";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T1 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:22:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 1 CORRECT 1 "s1=v1*tb" WRITE-SDD USNA SP212 General Physics II 53 (= dist_PULSE_23 (* sp_PULSE_23 t_23)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:22:32.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 10 INCORRECT 2 "v" Unable to solve for v. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:23:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-SPEED USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 CORRECT Var-12 label="vc";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_23)) 1 CORRECT 2 "(s+s1)=vc*t" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 2 CORRECT 2 "(s+s1)=vc*t" WRITE-SDD USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 1 CORRECT 2 "(s+s1)=vc*t" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_12)) 1 CORRECT 2 "(s+s1)=vc*t" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 2 CORRECT 2 "(s+s1)=vc*t" WRITE-SDD USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:24:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= t_13 (+ t_12 t_23))) 1 CORRECT 2 "(s+s1)=vc*t" WRITE-SUM-TIMES USNA SP212 General Physics II (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:00.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 11 INCORRECT 3 "vc" Unable to solve for vc. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:05.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 12 INCORRECT 3 "t" Unable to solve for t. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT You should be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II 48 DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-13 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 2 "(s2)=vc*t" WRITE-SDD USNA SP212 General Physics II (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 CORRECT 2 "s2=vc*t" WRITE-SDD USNA SP212 General Physics II (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 13 INCORRECT 3 "t" Unable to solve for t. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:25:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 3 "vc=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:07.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 14 INCORRECT 4 "t" Unable to solve for t. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Write the equation ?T02-VAR = s + s1. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 43 DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:44.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 INCORRECT 4 "a2=s1+s" Undefined variable: a2 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 CORRECT 4 "s2=s1+s" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_23 dist_PULSE_12)) DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 15 CORRECT 5 "t" USNA SP212 General Physics II DD517 DD517-Apr10-15-14-59 2007-04-10 16:26:57.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 74 DD517 DD517-Apr10-15-27-33 2007-04-10 16:27:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD517 DD517-Apr10-15-27-33 2007-04-10 16:28:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 12 DD517 DD517-Apr10-15-27-33 2007-04-10 16:28:16.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 2 HINT Var-2 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:28:40.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 INCORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=180;mag=233 DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 11 DD517 DD517-Apr10-15-27-33 2007-04-10 16:28:45.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=233 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 12 DD517 DD517-Apr10-15-27-33 2007-04-10 16:28:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD517 DD517-Apr10-15-27-33 2007-04-10 16:29:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:23.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:31.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:30:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 18 DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:01.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-6 label="T";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 13 DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:22.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-7 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 14 DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:31:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 9 DD517 DD517-Apr10-15-27-33 2007-04-10 16:32:03.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 53 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD517 DD517-Apr10-15-27-33 2007-04-10 16:32:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 INCORRECT 2 "r_x" Although you seem to have enough equations, the Andes solver is unable to solve them for r_x in their current form. Try entering algebraic combinations to isolate a calculable expression for r_x yourself. Combining equations and plugging in numbers for variables, solving for intermediate unknowns if needed, might get you closer to a form that Andes can solve. If not, you will just have to finish the problem on your own. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:32:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DD517 DD517-Apr10-15-27-33 2007-04-10 16:32:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 84 DD517 DD517-Apr10-15-33-05 2007-04-10 16:34:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:34:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=all forces;time=T0;value="2MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:34:57.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT Var-1 label=P Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=electric_output;time=T0;value="2MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:11.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 HINT Var-1 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 6 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 7 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 2 DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:27.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT Var-1 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:35:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 12 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:37:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=all sources;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 DD517 DD517-Apr10-15-33-05 2007-04-10 16:37:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 21 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:38:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 INCORRECT Var-4 label="A";quant=area;subtype=NIL;body=sunlight;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:38:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 22 DD517 DD517-Apr10-15-33-05 2007-04-10 16:38:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT 0 "P=I*A" DEFINE-POWER-VAR USNA SP212 General Physics II 21 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:39:07.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT 0 "P=I*2*A" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* int_COLLECTOR_SUNLIGHT_1 2) A_COLLECTOR)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:39:17.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT 0 What equation do you wish to write? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:40:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:40:27.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:41:30.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT spherical-intensity-to-power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:41:39.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:41:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 5 5 DEFINE-POWER-VAR USNA SP212 General Physics II 16 DD517 DD517-Apr10-15-33-05 2007-04-10 16:41:53.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 INCORRECT 0 "P=I*A" DEFINE-POWER-VAR USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:42:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 10 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:42:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P1=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 60 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P1=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:32.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 1 "P1=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:33.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 1 What equation do you wish to write? 1 GIVEN-FRACTION USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:38.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 HINT uniform-intensity-to-power Equations of that type appear within the problem solution. You should write the equation in the form P = I*A using your own variables. If you do not want to write this equation and are not sure what to do, why don't you call Light-Bulb-Help. 2 2 GIVEN-FRACTION USNA SP212 General Physics II 55 DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 5 HINT Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 6 HINT You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:43:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 7 HINT Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 50 DD517 DD517-Apr10-15-33-05 2007-04-10 16:44:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 8 CORRECT 1 ".28*P1=P" GIVEN-FRACTION USNA SP212 General Physics II (= (* 0.28 power_COLLECTOR_SUNLIGHT_1) power_ELECTRIC_OUTPUT_COLLECTOR_1) DD517 DD517-Apr10-15-33-05 2007-04-10 16:44:12.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD517 DD517-Apr10-15-33-05 2007-04-10 16:44:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 81 DD517 DD517-Apr10-15-44-30 2007-04-10 16:46:39.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:46:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD517 DD517-Apr10-15-44-30 2007-04-10 16:47:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 12 DD517 DD517-Apr10-15-44-30 2007-04-10 16:47:32.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 11 DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:08.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 INCORRECT Vector-4 label="F";type=Force;body=sail;agent=Unspecified;forcetype=Pressure;time=T0;dir=360;mag=69 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:09.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-4 label=F Is the force is due to an unspecified agent? 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Axes-6 label=NIL Forces are caused by interacting objects. The force can either be a field force, such as weight, in which case the objects do not have to touch. Or the force is a contact force, such as tension or friction, in which case the objects must touch. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Axes-6 label=NIL Draw a pressure force on the sail at T0, but make it be due to the sunlight instead of an unspecified agent. 3 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 6 DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:31.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 INCORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=360;mag=69 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 5 DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:37.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 INCORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=69 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:41.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-4 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Axes-6 label=NIL Double-click on the vector in order to bring up its properties, then erase the number in the direction box to mark the direction unknown. 2 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:48:52.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=69 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:52:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 20 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD517 DD517-Apr10-15-44-30 2007-04-10 16:52:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 21 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD517 DD517-Apr10-15-44-30 2007-04-10 16:52:55.0 US/Eastern CALC_REQUEST Simplify CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P=2*I/c" USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:53:02.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 INCORRECT Answer-1 "2600 kg/s^3" Units are inconsistent. 1 1 USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:53:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 2 "P" USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:53:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 CORRECT Answer-1 " 8.672666475151953e-6 Pa" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 34 DD517 DD517-Apr10-15-44-30 2007-04-10 16:53:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 CORRECT 3 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 43 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD517 DD517-Apr10-15-44-30 2007-04-10 16:54:03.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 INCORRECT 4 "P=F/A" Undefined variable: A 1 DEFINE-AREA USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:54:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:54:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 4 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 63 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DD517 DD517-Apr10-15-44-30 2007-04-10 16:54:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 5 "A" USNA SP212 General Physics II DD517 DD517-Apr10-15-44-30 2007-04-10 16:54:22.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 75 DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:12.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 (= ampE_WAVE (DNUM 120 V/m)) DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "B=E/c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= ampM_WAVE (/ ampE_WAVE c)) DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:44.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD54D DD54D-Apr17-12-48-40 2007-04-17 13:50:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 " 4.0027691423778244e-7 T" USNA SP212 General Physics II 98 DD54D DD54D-Apr17-12-51-11 2007-04-17 13:52:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:52:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD54D DD54D-Apr17-12-51-11 2007-04-17 13:52:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:52:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD54D DD54D-Apr17-12-51-11 2007-04-17 13:53:15.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-5 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=236 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:53:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD54D DD54D-Apr17-12-51-11 2007-04-17 13:53:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-6 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:53:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:53:51.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:03.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT energy-decay No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:20.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT period-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 6 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 7 CORRECT System-7 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:44.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 CORRECT System-8 label="transmitter";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:54:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:55:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 CORRECT 1 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DD54D DD54D-Apr17-12-51-11 2007-04-17 13:55:25.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD54D DD54D-Apr17-12-51-11 2007-04-17 13:55:31.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 100 DD54D DD54D-Apr17-12-56-05 2007-04-17 13:56:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD54D DD54D-Apr17-12-56-05 2007-04-17 13:57:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD54D DD54D-Apr17-12-56-05 2007-04-17 13:57:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 25 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD54D DD54D-Apr17-12-56-05 2007-04-17 13:57:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=A*I*0.28" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 GIVEN-FRACTION USNA SP212 General Physics II 50 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1) 0.28)) DD54D DD54D-Apr17-12-56-05 2007-04-17 13:57:55.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=A*I*0.28" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 50 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1) 0.28)) DD54D DD54D-Apr17-12-56-05 2007-04-17 13:58:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 1 "A" USNA SP212 General Physics II DD54D DD54D-Apr17-12-56-05 2007-04-17 13:58:36.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476191 m^2" USNA SP212 General Physics II 81 DD54D DD54D-Apr17-12-58-53 2007-04-17 13:59:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-1 label="Psail";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 6 DD54D DD54D-Apr17-12-58-53 2007-04-17 13:59:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD54D DD54D-Apr17-12-58-53 2007-04-17 14:00:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT Var-3 label="n";quant=index-of-refraction;subtype=NIL;body=sail;agent=NIL;time=NIL;value="0" DRAW-BODY USNA SP212 General Physics II 12 DD54D DD54D-Apr17-12-58-53 2007-04-17 14:00:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 INCORRECT Var-3 label="n";quant=index-of-refraction;subtype=NIL;body=sail;agent=NIL;time=NIL;value="1" DRAW-BODY USNA SP212 General Physics II 11 DD54D DD54D-Apr17-12-58-53 2007-04-17 14:00:13.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT Var-3 label=n Although you can always define a index-of-refraction variable, none are needed for any solution I know of this problem. 1 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:00:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:01.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 5 INCORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-BODY USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:08.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 6 CORRECT System-5 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 22 DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:22.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=135 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:25.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-6 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:31.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=135 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:39.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 31 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-AREA USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:01:57.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-AREA USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:09.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT pressure-force Right indeed. A good step would be introducing a variable for the area of the sail. 3 DEFINE-AREA USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation Psail = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 26 DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "Psail=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 46 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "Psail" USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:02:57.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 62 DD54D DD54D-Apr17-12-58-53 2007-04-17 14:03:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 CORRECT 3 "Psail=F/A" PRESSURE-FORCE USNA SP212 General Physics II 82 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DD54D DD54D-Apr17-12-58-53 2007-04-17 14:03:15.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DD54D DD54D-Apr17-12-58-53 2007-04-17 14:03:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 93 DD54D DD54D-Apr17-13-03-39 2007-04-17 14:04:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 CORRECT Var-2 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 25 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-3 label="stot";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:20.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "stot=s+s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-4 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 1 "t=stot/c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 69 (= t_13 (/ dist_PULSE_13 c)) DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "t=stot/c" WRITE-SDD USNA SP212 General Physics II 69 (= t_13 (/ dist_PULSE_13 c)) DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:37.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DD54D DD54D-Apr17-13-03-39 2007-04-17 14:05:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 100 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:54:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=P;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II DD60D DD60D-Apr22-15-54-14 2007-04-22 16:54:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 12 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD60D DD60D-Apr22-15-54-14 2007-04-22 16:55:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 1 INCORRECT Var-3 label="L";quant=length;subtype=NIL;body=transmitter;agent=NIL;time=NIL;value="8 km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 11 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:55:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 2 INCORRECT Var-3 label="L";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8 km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II DD60D DD60D-Apr22-15-54-14 2007-04-22 16:55:35.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT Var-3 label=L This problem should be solved by drawing relative position vectors. Although the length you've defined might have the same value as the magnitude of a relative position, it is an Andes convention to use quantities that appear in the principles whenever possible. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD60D DD60D-Apr22-15-54-14 2007-04-22 16:55:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Try drawing, for instance, the relative position of the transmitter with respect to P. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:55:54.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 7 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:56:06.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-5 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II 8 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:56:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 3 INCORRECT Var-3 label="L";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8 km" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 7 DD60D DD60D-Apr22-15-54-14 2007-04-22 16:56:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Var-6 1 INCORRECT Var-6 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8 km" USNA SP212 General Physics II DD60D DD60D-Apr22-15-54-14 2007-04-22 16:56:40.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A Var-6 2 HINT Var-6 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 USNA SP212 General Physics II DD60D DD60D-Apr23-14-38-23 2007-04-23 15:39:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DD60D DD60D-Apr23-14-38-23 2007-04-23 15:39:33.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DD60D DD60D-Apr23-14-38-23 2007-04-23 15:39:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 14 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD60D DD60D-Apr23-14-38-23 2007-04-23 15:40:37.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 INCORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=NIL;mag=234 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 12 DD60D DD60D-Apr23-14-38-23 2007-04-23 15:40:41.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Vector-3 label=r Do you really want the direction of that vector to be unknown? 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD60D DD60D-Apr23-14-38-23 2007-04-23 15:40:54.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=234 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 13 DD60D DD60D-Apr23-14-38-23 2007-04-23 15:41:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD60D DD60D-Apr23-14-38-23 2007-04-23 15:42:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 67 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DD60D DD60D-Apr23-14-38-23 2007-04-23 15:42:32.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD60D DD60D-Apr23-14-38-23 2007-04-23 15:42:39.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 98 DD60D DD60D-Apr23-20-21-54 2007-04-23 21:22:21.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD60D DD60D-Apr23-20-21-54 2007-04-23 21:22:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD60D DD60D-Apr23-20-21-54 2007-04-23 21:23:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 12 DD60D DD60D-Apr23-20-21-54 2007-04-23 21:23:45.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 INCORRECT 0 "P=I/C" Undefined variable: C 1 DEFINE-AREA USNA SP212 General Physics II 11 DD60D DD60D-Apr23-20-21-54 2007-04-23 21:23:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 INCORRECT 0 "P=I/c" DEFINE-AREA USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DD60D DD60D-Apr23-20-21-54 2007-04-23 21:24:14.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 INCORRECT 0 "P=S/c" Undefined variable: S 1 DEFINE-AREA USNA SP212 General Physics II 10 DD60D DD60D-Apr23-20-21-54 2007-04-23 21:25:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 11 DD60D DD60D-Apr23-20-21-54 2007-04-23 21:25:12.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "P=20mN/A" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 28 (= Pr_SAIL (/ (DNUM 20 mN) A_SAIL)) DD60D DD60D-Apr23-20-21-54 2007-04-23 21:25:12.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 0 "P=20mN/A" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 PRESSURE-FORCE USNA SP212 General Physics II 28 (= Pr_SAIL (/ (DNUM 20 mN) A_SAIL)) DD60D DD60D-Apr23-20-21-54 2007-04-23 21:28:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 1 1 INCORRECT 1 "P=I/c" USNA SP212 General Physics II 27 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DD60D DD60D-Apr23-20-21-54 2007-04-23 21:28:31.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE5 1 2 HINT 1 What equation do you wish to write? 1 USNA SP212 General Physics II DD60D DD60D-Apr23-20-21-54 2007-04-23 21:29:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 Unknown 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 USNA SP212 General Physics II DD60D DD60D-Apr23-20-21-54 2007-04-23 21:29:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 Unknown 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 22 DD71E DD71E-May08-00-02-09 2007-05-08 01:03:24.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Answer-1 "120" Forgot to put units on a number. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:03:28.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 INCORRECT Answer-1 "120 V" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:03:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:03:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:03:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 5 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:03:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 6 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 4 4 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DD71E DD71E-May08-00-02-09 2007-05-08 01:03:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 7 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 20 (= ampE_WAVE (DNUM 120 V/m)) DD71E DD71E-May08-00-02-09 2007-05-08 01:04:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:04:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:04:09.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:04:29.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT electromagnetic-wave-field-amplitude Good! Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:04:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT Write the equation E = c * B. 4 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 15 DD71E DD71E-May08-00-02-09 2007-05-08 01:04:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 CORRECT 0 "E = c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 59 (= ampE_WAVE (* c ampM_WAVE)) DD71E DD71E-May08-00-02-09 2007-05-08 01:04:38.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD71E DD71E-May08-00-02-09 2007-05-08 01:04:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 86 DD71E DD71E-May08-00-04-54 2007-05-08 01:05:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD71E DD71E-May08-00-04-54 2007-05-08 01:05:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DD71E DD71E-May08-00-04-54 2007-05-08 01:05:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 3 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 4 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -4 DD71E DD71E-May08-00-04-54 2007-05-08 01:05:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DD71E DD71E-May08-00-04-54 2007-05-08 01:05:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 4 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD71E DD71E-May08-00-04-54 2007-05-08 01:05:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:05:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II -1 DD71E DD71E-May08-00-04-54 2007-05-08 01:06:08.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=238 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:06:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:06:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:06:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:06:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -6 DD71E DD71E-May08-00-04-54 2007-05-08 01:06:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 CORRECT 0 "r = 8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD71E DD71E-May08-00-04-54 2007-05-08 01:06:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:06:35.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:13.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:14.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT A good step would be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 6 6 DEFINE-INTENSITY USNA SP212 General Physics II -1 DD71E DD71E-May08-00-04-54 2007-05-08 01:07:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -6 DD71E DD71E-May08-00-04-54 2007-05-08 01:07:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:37.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-5 label="T";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -11 DD71E DD71E-May08-00-04-54 2007-05-08 01:07:47.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-6 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:07:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -16 DD71E DD71E-May08-00-04-54 2007-05-08 01:08:03.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 INCORRECT 1 "P = 4*pi*(r^2)*I" Undefined variable: pi 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:08:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 6 CORRECT 1 "P = 4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 28 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD71E DD71E-May08-00-04-54 2007-05-08 01:08:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 23 DD71E DD71E-May08-00-04-54 2007-05-08 01:08:22.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DD71E DD71E-May08-00-04-54 2007-05-08 01:08:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 54 DD71E DD71E-May08-00-08-41 2007-05-08 01:08:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:08:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD71E DD71E-May08-00-08-41 2007-05-08 01:08:51.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DD71E DD71E-May08-00-08-41 2007-05-08 01:08:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:08:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:08:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:08:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -4 DD71E DD71E-May08-00-08-41 2007-05-08 01:09:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 6 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD71E DD71E-May08-00-08-41 2007-05-08 01:09:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 1 DD71E DD71E-May08-00-08-41 2007-05-08 01:09:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 10 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD71E DD71E-May08-00-08-41 2007-05-08 01:09:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:45.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:53.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT electric-flux-constant-field No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:54.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT point-charge-efield-mag No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT Try introducing a variable for the power supplied to the collector from the sunlight at T0. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:09:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 6 6 DEFINE-POWER-VAR USNA SP212 General Physics II 5 DD71E DD71E-May08-00-08-41 2007-05-08 01:10:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 CORRECT Var-4 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Your goal should be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -5 DD71E DD71E-May08-00-08-41 2007-05-08 01:10:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P1 = A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 39 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DD71E DD71E-May08-00-08-41 2007-05-08 01:10:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 34 DD71E DD71E-May08-00-08-41 2007-05-08 01:10:51.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P = 0.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD71E DD71E-May08-00-08-41 2007-05-08 01:10:54.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD71E DD71E-May08-00-08-41 2007-05-08 01:10:58.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 65 DD71E DD71E-May08-00-11-08 2007-05-08 01:11:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DD71E DD71E-May08-00-11-08 2007-05-08 01:11:24.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-1 label="Sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DD71E DD71E-May08-00-11-08 2007-05-08 01:11:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 3 HINT Try introducing a variable for the intensity supplied to the sail at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 4 HINT Define a variable for the intensity supplied to the sail at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II 7 DD71E DD71E-May08-00-11-08 2007-05-08 01:11:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DD71E DD71E-May08-00-11-08 2007-05-08 01:11:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 13 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD71E DD71E-May08-00-11-08 2007-05-08 01:11:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:11:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 8 DD71E DD71E-May08-00-11-08 2007-05-08 01:12:14.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-3 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=101 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 9 DD71E DD71E-May08-00-11-08 2007-05-08 01:12:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DD71E DD71E-May08-00-11-08 2007-05-08 01:12:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F = 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 12 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD71E DD71E-May08-00-11-08 2007-05-08 01:12:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:31.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:37.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT radiation-pressure That's right. Try introducing a variable for the pressure at the sail at T0. 3 DEFINE-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT Define a variable for the pressure at the sail at T0 by using the Add Variable command on the Variable menu and selecting Pressure. 4 4 DEFINE-PRESSURE USNA SP212 General Physics II 7 DD71E DD71E-May08-00-11-08 2007-05-08 01:12:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 CORRECT Var-4 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:12:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 2 DD71E DD71E-May08-00-11-08 2007-05-08 01:12:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P = (2*I) / c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 22 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD71E DD71E-May08-00-11-08 2007-05-08 01:13:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:13:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 39 DD71E DD71E-May08-00-11-08 2007-05-08 01:13:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:13:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "A = F/P" PRESSURE-FORCE USNA SP212 General Physics II 58 (= A_SAIL (/ Fp_SAIL_SUNLIGHT_1 Pr_SAIL)) DD71E DD71E-May08-00-11-08 2007-05-08 01:13:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DD71E DD71E-May08-00-11-08 2007-05-08 01:13:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 69 DD71E DD71E-May08-00-14-43 2007-05-08 01:14:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:14:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:02.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="P";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:11.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -9 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 5 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 1 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD71E DD71E-May08-00-14-43 2007-05-08 01:15:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:15:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -4 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:47.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s1 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -6 DD71E DD71E-May08-00-14-43 2007-05-08 01:15:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 4 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD71E DD71E-May08-00-14-43 2007-05-08 01:16:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Yep. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT speed-equals-wave-speed That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:42.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT wave-speed-string No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT You should be introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:16:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II -1 DD71E DD71E-May08-00-14-43 2007-05-08 01:17:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 9 CORRECT Var-5 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT A good step would be introducing a variable for the distance travelled by the pulse from T0 to T2. 3 DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T2. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -6 DD71E DD71E-May08-00-14-43 2007-05-08 01:17:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 CORRECT Var-6 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s2 = s+s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DD71E DD71E-May08-00-14-43 2007-05-08 01:17:36.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 INCORRECT 1 "s2 = v*t" Undefined variable: t 1 DEFINE-DURATION USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:17:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "s2 = v*t" WRITE-SDD USNA SP212 General Physics II 38 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DD71E DD71E-May08-00-14-43 2007-05-08 01:17:52.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 2 "v = c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD71E DD71E-May08-00-14-43 2007-05-08 01:17:55.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "t" USNA SP212 General Physics II DD71E DD71E-May08-00-14-43 2007-05-08 01:18:01.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 69 DD7E7 DD7E7-May07-17-47-05 2007-05-07 18:47:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DD7E7 DD7E7-May07-17-47-05 2007-05-07 18:47:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:05:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:05:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:05:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:05:44.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:06:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT wave-speed-light No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:07:31.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:07:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:07:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:07:59.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:08:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-04-29 2007-04-23 22:08:17.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 " 4.0027691423778244e-7 T" USNA SP212 General Physics II 95 DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:09:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 1 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T1;value="" DEFINE-DURATION USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:32.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 1 CORRECT 0 "t=s/c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 38 (= t_12 (/ dist_PULSE_12 c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:32.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 0 "t=s/c" WRITE-SDD USNA SP212 General Physics II 38 (= t_12 (/ dist_PULSE_12 c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:36.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 1 "t" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:46.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT Answer-1 "1.280886125560904 s" DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:10:50.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT Answer-1 label=1.280886125560904 s 1.280886125560904 s is not the correct value for the duration of the interval from T0 to T2. When you have entered enough equations, ask Andes to solve for the duration of the interval from T0 to T2, then transfer the result to this answer box. 1 1 DRAW-BODY USNA SP212 General Physics II 32 DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:11:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:11:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 26 DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:11:25.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 CORRECT System-3 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:11:37.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:11:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:12:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 DEFINE-DISTANCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 CORRECT Var-6 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 36 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 INCORRECT 0 "t=(s+s1)/c" DEFINE-DURATION USNA SP212 General Physics II 13 (= t_12 (/ (+ dist_PULSE_12 dist_PULSE_23) c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 14 DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:38.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "t=(s+s1)/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 39 (= t_13 (/ (+ dist_PULSE_12 dist_PULSE_23) c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:38.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "t=(s+s1)/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 39 (= t_13 (/ (+ dist_PULSE_12 dist_PULSE_23) c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:38.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "t=(s+s1)/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 39 (= t_13 (/ (+ dist_PULSE_12 dist_PULSE_23) c)) DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 HINT It is good practice to identify the fundamental principles you are using by writing them purely symbolically in standard form before combining them with other equations or given values. Select "Review Physics Equations" on the Help Menu to view a list of principles and their standard forms. 2 USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:13:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 CORRECT 1 "t" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-09-04 2007-04-23 22:14:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 67 DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:15:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:16:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-5 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=231 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:16:39.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:17:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-6 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 25 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:17:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:17:26.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-7 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:17:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:17:39.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:19:17.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT energy-decay No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:19:51.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT uniform-intensity-to-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:19:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:19:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 20 DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:13.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-8 label="T";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:29.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-9 label="Point";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:20:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 15 DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:21:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 59 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:21:37.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-14-25 2007-04-23 22:21:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 90 DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:25:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:26:21.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II 12 DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:26:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 14 DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:26:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:09.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 9 DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:20.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 4 DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-5 label="P1";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 14 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:27:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:28:09.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:28:39.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT uniform-intensity-to-power Good! If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:29:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 INCORRECT 0 "P1=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 13 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:29:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 57 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:29:34.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P1=p*.28" Undefined variable: p 1 GIVEN-FRACTION USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:29:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 1 "P1=P*.28" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* power_COLLECTOR_SUNLIGHT_1 0.28)) DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:29:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-22-44 2007-04-23 22:30:07.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 88 DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:31:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:32:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:32:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 33 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:33:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:33:15.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 " 8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 50 DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:34:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:35:36.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=135 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:37:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:37:27.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 CORRECT System-6 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 61 DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:37:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:37:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 CORRECT 2 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 69 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:37:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:38:15.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT #.(wb-quant '(define-variable "F" |Pressure| |force| |sail| |T0| |sunlight| NIL "") 'mag) That quantity is not sought by the problem statement. 2 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:38:28.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT #.(wb-quant '(define-variable "F" |Thrust| |force| |sail| |T0| |sunlight| NIL "") 'mag) That quantity is not mentioned in the Andes solution. 3 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:38:40.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |sail| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 4 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:39:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 5 HINT radiation-pressure That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 5 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:39:55.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 6 HINT intensity-to-decibels No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the pressure. 6 PRESSURE-FORCE USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:39:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 7 HINT Write the equation F = P * A 7 7 PRESSURE-FORCE USNA SP212 General Physics II 64 DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:40:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 8 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 84 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:40:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "F" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:40:22.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DD7F9 DD7F9-Apr23-21-30-30 2007-04-23 22:40:36.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 95 DD925 DD925-Apr30-11-13-14 2007-04-30 12:14:23.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Answer-1 "120V/m" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:14:36.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 INCORRECT Answer-1 "120 T" DEFINE-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:14:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:15:00.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V" Units are inconsistent. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II (= ampE_WAVE (DNUM 120 V)) DD925 DD925-Apr30-11-13-14 2007-04-30 12:15:12.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 5 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:15:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 6 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 21 (= ampE_WAVE (DNUM 120 V/m)) DD925 DD925-Apr30-11-13-14 2007-04-30 12:15:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-3 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 DD925 DD925-Apr30-11-13-14 2007-04-30 12:16:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:17:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:17:32.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:17:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT electromagnetic-wave-field-amplitude Right indeed. Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:18:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 66 (= ampE_WAVE (* ampM_WAVE c)) DD925 DD925-Apr30-11-13-14 2007-04-30 12:18:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD925 DD925-Apr30-11-13-14 2007-04-30 12:18:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DD925 DD925-Apr30-15-09-36 2007-04-30 16:10:31.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD925 DD925-Apr30-15-09-36 2007-04-30 16:10:36.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:11:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:12:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD925 DD925-Apr30-15-09-36 2007-04-30 16:12:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:12:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:12:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:13:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 CORRECT Vector-7 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=235 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:13:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DD925 DD925-Apr30-15-09-36 2007-04-30 16:15:56.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD925 DD925-Apr30-15-09-36 2007-04-30 16:16:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD925 DD925-Apr30-15-09-36 2007-04-30 16:16:22.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 100 DD925 DD925-Apr30-15-19-01 2007-04-30 16:20:22.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DD925 DD925-Apr30-15-19-01 2007-04-30 16:20:53.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0 MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 2 DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 3 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0 MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:27.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 4 HINT Var-2 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 5 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 6 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 7 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:21:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 8 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -3 DD925 DD925-Apr30-15-19-01 2007-04-30 16:22:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=electric_output;time=T0;value="" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -4 DD925 DD925-Apr30-15-19-01 2007-04-30 16:22:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=all sources;time=T0;value="" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:22:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=collector;time=T0;value="" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:22:31.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:23:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 6 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD925 DD925-Apr30-15-19-01 2007-04-30 16:23:47.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2.0 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 5 DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 4 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 5 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:39.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-5 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:24:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-5 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0MW" DEFINE-POWER-VAR USNA SP212 General Physics II 10 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DD925 DD925-Apr30-15-19-01 2007-04-30 16:25:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:25:18.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:25:35.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT uniform-intensity-to-power Yep. You should be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:25:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-6 label="P2";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-7 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 11 DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 0 "P=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 0 "P2=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 55 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 INCORRECT 1 "A" Unable to solve for A. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P2=P" GIVEN-FRACTION USNA SP212 General Physics II 54 (= power_COLLECTOR_SUNLIGHT_1 power_ELECTRIC_OUTPUT_COLLECTOR_1) DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:26:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 HINT 0 Write the equation P = 0.28 * P2 3 3 GIVEN-FRACTION USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:27:21.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 1 "P=.28*P2" GIVEN-FRACTION USNA SP212 General Physics II 55 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD925 DD925-Apr30-15-19-01 2007-04-30 16:27:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DD925 DD925-Apr30-15-19-01 2007-04-30 16:27:40.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 86 DD925 DD925-Apr30-15-27-59 2007-04-30 16:35:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-1 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 6 DD925 DD925-Apr30-15-27-59 2007-04-30 16:36:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:36:24.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 1 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 4 DD925 DD925-Apr30-15-27-59 2007-04-30 16:37:07.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DD925 DD925-Apr30-15-27-59 2007-04-30 16:37:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:37:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT 0 "P=A*I" Units are inconsistent. 1 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 11 (= Pr_SAIL (* A_SAIL int_SAIL_SUNLIGHT_1)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:39:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:23.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Applied;time=T0;dir=NIL;mag=307 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 10 DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:26.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F There is indeed a force on the sail due to the sunlight, but it is not a applied force. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-6 label=F It is a pressure force 2 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 5 DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:39.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=307 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 6 DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 1 DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:53.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-6 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:40:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 7 DD925 DD925-Apr30-15-27-59 2007-04-30 16:41:10.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 16 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:42:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 PRESSURE-FORCE USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:42:26.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 PRESSURE-FORCE USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:42:34.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT pressure-force Yep. Write the equation F = P * A 3 3 PRESSURE-FORCE USNA SP212 General Physics II 11 DD925 DD925-Apr30-15-27-59 2007-04-30 16:42:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 1 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 30 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:42:53.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 INCORRECT 2 "P" Unable to solve for P. Try the light-bulb if you need a hint about a step that still needs to be done. 1 USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 25 DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 2 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 45 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:41.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 3 "P" USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:48.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT Answer-1 " 8.672666475151953e-6 Pa" USNA SP212 General Physics II 62 DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 5 CORRECT 4 "A" USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:58.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 6 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 73 DD925 DD925-Apr30-15-27-59 2007-04-30 16:43:58.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 6 INCORRECT 4 "A = " Syntax error in A = 1 USNA SP212 General Physics II ? DD925 DD925-Apr30-15-27-59 2007-04-30 16:44:13.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 7 CORRECT 4 "A" USNA SP212 General Physics II DD925 DD925-Apr30-15-27-59 2007-04-30 16:44:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 7 CORRECT 4 "A = 2306.095830769231 m^2" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 73 (= A_SAIL (DNUM 2306.095830769231 m^2)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:44:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 5 CORRECT 4 "A = 2306.095830769231 m^2" PRESSURE-FORCE USNA SP212 General Physics II 73 (= A_SAIL (DNUM 2306.095830769231 m^2)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:44:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2))) 2 CORRECT 4 "A = 2306.095830769231 m^2" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 73 (= A_SAIL (DNUM 2306.095830769231 m^2)) DD925 DD925-Apr30-15-27-59 2007-04-30 16:44:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 CORRECT 4 "A = 2306.095830769231 m^2" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 73 (= A_SAIL (DNUM 2306.095830769231 m^2)) DD961 DD961-Apr22-20-16-52 2007-04-22 21:17:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DD961 DD961-Apr22-20-16-52 2007-04-22 21:17:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DD961 DD961-Apr22-20-16-52 2007-04-22 21:17:58.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 INCORRECT System-3 label="w";body=wave;time=NIL WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 23 DD961 DD961-Apr22-20-16-52 2007-04-22 21:18:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 CORRECT 0 "E = B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= ampE_WAVE (* ampM_WAVE c)) DD961 DD961-Apr22-20-16-52 2007-04-22 21:18:41.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DD961 DD961-Apr22-20-16-52 2007-04-22 21:18:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0028e-7 T" USNA SP212 General Physics II 98 DD961 DD961-Apr22-20-24-27 2007-04-22 21:24:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DD961 DD961-Apr22-20-24-27 2007-04-22 21:25:14.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=237 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DD961 DD961-Apr22-20-24-27 2007-04-22 21:25:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DD961 DD961-Apr22-20-24-27 2007-04-22 21:26:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DD961 DD961-Apr22-20-24-27 2007-04-22 21:28:25.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P = 4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DD961 DD961-Apr22-20-24-27 2007-04-22 21:28:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DD961 DD961-Apr22-20-24-27 2007-04-22 21:28:39.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.482e-4 W/m^2" USNA SP212 General Physics II 100 DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -5 DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:29.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 1 DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:30:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DD961 DD961-Apr22-20-28-58 2007-04-22 21:31:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:31:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-6 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 20 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DD961 DD961-Apr22-20-28-58 2007-04-22 21:32:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:32:16.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:32:38.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:32:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-7 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:33:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 INCORRECT 0 "P1 = .28*P" DEFINE-AREA USNA SP212 General Physics II 19 (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DD961 DD961-Apr22-20-28-58 2007-04-22 21:33:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:33:51.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-8 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:33:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:18.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT System-9 label="x";body=collector;time=NIL WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "I = P1/A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= int_COLLECTOR_SUNLIGHT_1 (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:48.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:34:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:35:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 1 "P = .28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DD961 DD961-Apr22-20-28-58 2007-04-22 21:35:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DD961 DD961-Apr22-20-28-58 2007-04-22 21:35:28.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476 m^2" USNA SP212 General Physics II 93 DD961 DD961-Apr22-20-35-47 2007-04-22 21:35:56.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DEFINE-INTENSITY USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:36:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 11 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:36:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-3 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 12 DD961 DD961-Apr22-20-35-47 2007-04-22 21:36:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:37:01.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT 0 "I = P/A" Units are inconsistent. 1 1 DRAW-BODY USNA SP212 General Physics II (= int_SAIL_SUNLIGHT_1 (/ Pr_SAIL A_SAIL)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:37:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:37:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 6 DD961 DD961-Apr22-20-35-47 2007-04-22 21:37:42.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-5 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 18 DD961 DD961-Apr22-20-35-47 2007-04-22 21:40:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:40:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:41:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:41:24.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 INCORRECT Vector-7 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 17 DD961 DD961-Apr22-20-35-47 2007-04-22 21:41:26.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-7 label=F When the direction of a vector is not given or easily inferred from the problem statement, you should mark it unknown. Since drawing the vector automatically fills in a value for the vector's orientation angle, you have to erase this value in the dialog box to mark the direction unknown. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:41:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-7 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 18 DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 CORRECT 0 "F = 20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 26 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:42:48.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Yep. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:43:47.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT radiation-pressure Yes. the sunlight reflects off the sail. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:43:54.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 INCORRECT 1 "F = 2*I/c" Units are inconsistent. 1 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:43:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 CORRECT 1 "P = (2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 45 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:22.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:44:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 "8.673e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 62 DD961 DD961-Apr22-20-35-47 2007-04-22 21:45:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:45:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 57 DD961 DD961-Apr22-20-35-47 2007-04-22 21:45:14.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 3 "F = P*A" PRESSURE-FORCE USNA SP212 General Physics II 77 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DD961 DD961-Apr22-20-35-47 2007-04-22 21:45:22.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DD961 DD961-Apr22-20-35-47 2007-04-22 21:45:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.096 m^2" USNA SP212 General Physics II 88 DD961 DD961-Apr22-20-46-01 2007-04-22 21:46:22.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:46:24.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT System-1 label=e What other bodies can you define? 1 DRAW-BODY USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:46:34.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-1 label="m";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:46:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:47:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 CORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 11 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:47:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:47:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 6 DD961 DD961-Apr22-20-46-01 2007-04-22 21:47:34.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 6 CORRECT System-3 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 8 DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:17.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-5 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 18 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:48.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T1 to T2| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:48:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T1| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 3 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:49:04.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 4 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:49:26.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 5 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:50:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 6 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:50:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 7 DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:51:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-6 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:51:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:51:46.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s+s1 = v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 44 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:51:46.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "s+s1 = v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 44 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:52:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-8 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:52:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 CORRECT 0 "s2 = s+s1" WRITE-SUM-DISTANCES USNA SP212 General Physics II 19 (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:52:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 CORRECT 1 "s2 = v*t" WRITE-SDD USNA SP212 General Physics II 63 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DD961 DD961-Apr22-20-46-01 2007-04-22 21:52:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:53:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 2 "v = c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DD961 DD961-Apr22-20-46-01 2007-04-22 21:53:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "t" USNA SP212 General Physics II DD961 DD961-Apr22-20-46-01 2007-04-22 21:53:18.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.562 s" USNA SP212 General Physics II 94 DDA87 DDA87-May07-16-16-00 2007-05-07 17:16:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DDA87 DDA87-May07-16-16-00 2007-05-07 17:16:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DDA87 DDA87-May07-16-16-00 2007-05-07 17:16:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= (/ ampE_WAVE ampM_WAVE) c) DDA87 DDA87-May07-16-16-00 2007-05-07 17:16:32.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDA87 DDA87-May07-16-16-00 2007-05-07 17:16:39.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 " 4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DDA87 DDA87-May07-16-19-27 2007-05-07 17:20:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=all sources;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:20:20.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-1 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:20:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DDA87 DDA87-May07-16-19-27 2007-05-07 17:21:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 11 DDA87 DDA87-May07-16-19-27 2007-05-07 17:21:10.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT Var-2 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DEFINE-POWER-VAR USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:21:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=all forces;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:21:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:22:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 5 INCORRECT Var-2 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="" USNA SP212 General Physics II 10 DDA87 DDA87-May07-16-19-27 2007-05-07 17:22:13.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 6 HINT Var-2 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 USNA SP212 General Physics II DDA87 DDA87-May07-16-19-27 2007-05-07 17:22:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 Unknown 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 USNA SP212 General Physics II DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 7 CORRECT Var-2 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 21 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 ".28*(A*I)=P" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 GIVEN-FRACTION USNA SP212 General Physics II 47 (= (* 0.28 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) power_ELECTRIC_OUTPUT_COLLECTOR_1) DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 ".28*(A*I)=P" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 47 (= (* 0.28 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) power_ELECTRIC_OUTPUT_COLLECTOR_1) DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:35.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 1 "A" USNA SP212 General Physics II DDA87 DDA87-May07-16-23-08 2007-05-07 17:23:41.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476191 m^2" USNA SP212 General Physics II 78 DDA87 DDA87-May07-16-23-58 2007-05-07 17:25:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sunlight;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-23-58 2007-05-07 17:25:51.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 HINT Var-1 label=I Are you sure you want to choose the sunlight? 1 DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-23-58 2007-05-07 17:25:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 3 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sunlight;agent=all sources;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-23-58 2007-05-07 17:26:01.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 4 HINT Var-1 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DEFINE-INTENSITY USNA SP212 General Physics II DDA87 DDA87-May07-16-23-58 2007-05-07 17:26:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 5 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 10 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DDA87 DDA87-May07-16-23-58 2007-05-07 17:26:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 11 DDA87 DDA87-May07-16-23-58 2007-05-07 17:26:50.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 INCORRECT 0 "P=2I/c" Syntax error in P=2I/c 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II ? DDA87 DDA87-May07-16-23-58 2007-05-07 17:27:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 0 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 31 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DDA87 DDA87-May07-16-23-58 2007-05-07 17:27:05.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DDA87 DDA87-May07-16-23-58 2007-05-07 17:27:11.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 47 DDA87 DDA87-May07-16-29-02 2007-05-07 17:29:13.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 CORRECT System-3 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 59 DDA87 DDA87-May07-16-29-02 2007-05-07 17:29:31.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=204 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDA87 DDA87-May07-16-29-02 2007-05-07 17:29:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 2 "F= 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 68 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DDA87 DDA87-May07-16-29-02 2007-05-07 17:30:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DDA87 DDA87-May07-16-29-02 2007-05-07 17:30:02.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 87 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DDA87 DDA87-May07-16-29-02 2007-05-07 17:30:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DDA87 DDA87-May07-16-29-02 2007-05-07 17:30:13.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.0958307692313 m^2" USNA SP212 General Physics II 98 DDA87 DDA87-May07-16-30-40 2007-05-07 17:33:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 6 DDA87 DDA87-May07-16-30-40 2007-05-07 17:34:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:34:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-4 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 INCORRECT 0 "t=2*s1*c" Units are inconsistent. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 (= t_13 (* (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 CORRECT 0 "t=2*s1/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 46 (= t_13 (/ (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 0 "t=2*s1/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 46 (= t_13 (/ (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "t=2*s1/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 46 (= t_13 (/ (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "t=2*s1/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 46 (= t_13 (/ (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "t=2*s1/c" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 46 (= t_13 (/ (* 2 dist_PULSE_12) c)) DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 1 "t" USNA SP212 General Physics II DDA87 DDA87-May07-16-30-40 2007-05-07 17:35:48.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 77 DDD21 DDD21-May07-23-34-13 2007-05-08 00:34:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:34:59.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:10.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-1 label="e";body=(earth moon pulse);time=NIL DRAW-BODY USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:21.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 INCORRECT System-2 label="m";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 6 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:33.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 7 CORRECT System-3 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -3 DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:44.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 2 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 USNA SP212 General Physics II DDD21 DDD21-May07-23-34-13 2007-05-08 00:35:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 3 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 USNA SP212 General Physics II DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:35:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:36:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:36:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:39:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= ampE_WAVE (* ampM_WAVE c)) DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:39:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDD57 DDD57-Apr18-19-33-04 2007-04-18 20:39:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:41:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:41:50.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=232 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:41:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:42:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:45:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 69 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:45:56.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DDD57 DDD57-Apr18-19-40-37 2007-04-18 20:46:02.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 100 DDD57 DDD57-Apr18-19-58-46 2007-04-18 20:59:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84E8m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:00:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 1 CORRECT Var-2 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T1;value="" DEFINE-DURATION USNA SP212 General Physics II DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:11.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT 0 "s*c=t" Units are inconsistent. 1 1 DRAW-BODY USNA SP212 General Physics II 14 (= (* dist_PULSE_12 c) t_12) DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:44.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 INCORRECT System-3 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II 8 DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:47.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 HINT System-3 label=e What other bodies can you define? 1 DRAW-BODY USNA SP212 General Physics II DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:02:56.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 6 INCORRECT System-3 label="e";body=(earth pulse);time=NIL DRAW-BODY USNA SP212 General Physics II 7 DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:03:01.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 7 CORRECT System-3 label="e";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 8 DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:03:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:03:24.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD57 DDD57-Apr18-19-58-46 2007-04-18 21:03:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 Unknown 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:23:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:24:05.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-6 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s12 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:24:29.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 INCORRECT Var-6 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="1.92E8" Forgot to put units on a number. 1 DEFINE-DISTANCE USNA SP212 General Physics II 7 (= dist_PULSE_23 1.92e+8) DDD57 DDD57-May06-17-22-44 2007-05-06 18:24:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 INCORRECT Var-6 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="1.92E8m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_23 (DNUM 1.92e+8 m)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:25:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 CORRECT Var-6 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 17 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:25:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:25:46.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:26:56.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:27:04.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:27:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 CORRECT Var-8 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:28:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_13)) 1 CORRECT 0 "s=v*t" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II 39 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:28:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= wv_SPACE sp_PULSE_12)) 1 CORRECT 0 "s=v*t" SPEED-EQUALS-WAVE-SPEED USNA SP212 General Physics II 39 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:28:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 0 "s=v*t" WRITE-SDD USNA SP212 General Physics II 39 (= dist_PULSE_12 (* sp_PULSE_13 t_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:28:18.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 INCORRECT 1 "v" Unable to solve for v. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:29:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:29:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-9 label="t2";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:30:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 INCORRECT 1 "v*t2=s12" WRITE-SDD USNA SP212 General Physics II (= (* sp_PULSE_13 t_13) dist_PULSE_23) DDD57 DDD57-May06-17-22-44 2007-05-06 18:30:20.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT 1 Perhaps the variable s12 has the wrong time specification for this equation. 1 DEFINE-DISTANCE USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:30:55.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 CORRECT Var-10 label="st";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 CORRECT 1 "v*t2=st" WRITE-SDD USNA SP212 General Physics II 61 (= (* sp_PULSE_13 t_13) dist_PULSE_13) DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 CORRECT 2 "st=2*s" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 2 "st=2*s" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 2 "st=2*s" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (* 2 dist_PULSE_12)) DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:18.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "st" USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:31:48.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 INCORRECT 4 "t2" Unable to solve for t2. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:32:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:32:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 CORRECT 4 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DDD57 DDD57-May06-17-22-44 2007-05-06 18:32:54.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 4 CORRECT 5 "t2" USNA SP212 General Physics II DDD57 DDD57-May06-17-22-44 2007-05-06 18:33:00.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "t2 = 2.5617722511218077 s" USNA SP212 General Physics II 93 DDD57 DDD57-May07-17-53-28 2007-05-07 18:53:37.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT Answer-1 "7440.476190476189 m^2" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 48 DDD57 DDD57-May07-17-53-28 2007-05-07 18:53:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 0 "P1=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 93 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DDD57 DDD57-May07-17-58-21 2007-05-07 18:58:30.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 CORRECT System-5 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 24 DDD57 DDD57-May07-17-58-21 2007-05-07 18:58:48.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=180;mag=131 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 23 DDD57 DDD57-May07-17-58-21 2007-05-07 18:59:00.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=131 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD57 DDD57-May07-17-58-21 2007-05-07 18:59:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 32 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DDD57 DDD57-May07-17-58-21 2007-05-07 18:59:50.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 52 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DDD57 DDD57-May07-17-58-21 2007-05-07 18:59:55.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DDD57 DDD57-May07-17-58-21 2007-05-07 19:00:01.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 68 DDD57 DDD57-May07-17-58-21 2007-05-07 19:00:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 88 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DDD57 DDD57-May07-17-58-21 2007-05-07 19:00:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DDD57 DDD57-May07-17-58-21 2007-05-07 19:00:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.095830769231 m^2" USNA SP212 General Physics II 99 DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:26:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:26:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:26:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:26:54.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "E" |NIL| |amplitude-electric| |wave| |NIL| |NIL| NIL "") 'NIL) That quantity is not sought by the problem statement. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:27:00.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:27:18.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT electromagnetic-wave-field-amplitude Right indeed. A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:27:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:10.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 INCORRECT 0 "E/B=3.00E8 " The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 23 (= (/ ampE_WAVE ampM_WAVE) 3.0e+8) DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:21.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 INCORRECT 0 "E/B=3.00E8 m/s" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 22 (= (/ ampE_WAVE ampM_WAVE) (DNUM 3.0e+8 m/s)) DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:23.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT 0 What equation do you wish to write? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:25.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT electromagnetic-wave-field-amplitude Equations of that type appear within the problem solution. You should write the equation in the form E = B*c using your own variables. If you do not want to write this equation and are not sure what to do, why don't you call Light-Bulb-Help. 2 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 17 DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 61 (= ampE_WAVE (* ampM_WAVE c)) DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-25-26 2007-04-23 16:28:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 93 DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:30:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="38.4e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_12 (DNUM 3.84e+9 m)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:30:18.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT Var-2 label=s 3.84e+9 m is not the correct value for s. Reread the problem statement carefully to find the given value for s, the distance travelled by the pulse from T0 to T1. 1 DEFINE-DISTANCE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:30:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 12 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:30:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 2))) 1 CORRECT Var-3 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T1;value="" DEFINE-DURATION USNA SP212 General Physics II 14 DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 1 CORRECT 0 "t=s/c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 36 (= t_12 (/ dist_PULSE_12 c)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 1 CORRECT 0 "t=s/c" WRITE-SDD USNA SP212 General Physics II 36 (= t_12 (/ dist_PULSE_12 c)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 2 3))) 1 CORRECT Var-4 label="t1";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T1 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 1 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 1 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 2 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:31:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 2 CORRECT 1 "t=t1" Although equation 2 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 55 (= t_12 t_23) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-5 label="tt";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 2 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 2 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 3 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 3 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:19.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= t_13 (+ t_12 t_23))) 1 CORRECT 2 "tt=2*t" Although equation 3 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-TIMES USNA SP212 General Physics II (= t_13 (* 2 t_12)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 c)) 3 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_23 (/ dist_PULSE_23 t_23))) 3 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 3 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 c)) 4 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_12 (/ dist_PULSE_12 t_12))) 4 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:28.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= t_13 (+ t_12 t_23))) 2 CORRECT 3 "tt=2*t1" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-TIMES USNA SP212 General Physics II 56 (= t_13 (* 2 t_23)) DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT It is good practice to identify the fundamental principles you are using by writing them purely symbolically in standard form before combining them with other equations or given values. Select "Review Physics Equations" on the Help Menu to view a list of principles and their standard forms. 2 USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 4 "t" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:32:59.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 CORRECT 4 "tt" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-29-22 2007-04-23 16:33:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "tt = 2.5617722511218077 s" USNA SP212 General Physics II 87 DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:34:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:35:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-3 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:36:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-4 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 14 DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:36:05.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-4 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:36:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:37:05.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:37:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:37:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-6 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=132 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:37:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r= 8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 24 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:38:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:39:10.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:40:24.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT (magnetic-dipole-torque ((?axis . y))) No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:40:33.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:40:41.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 5 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:40:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 6 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 HINT You should use the body tool to draw a body choosing the transmitter as the body. 7 7 DRAW-BODY USNA SP212 General Physics II 19 DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:16.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 8 CORRECT System-7 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:30.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 CORRECT System-8 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:39.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 CORRECT Vector-6 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=132 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:41:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:42:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:42:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 14 DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:43:35.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 58 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:44:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-33-47 2007-04-23 16:44:05.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 89 DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:47:14.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:47:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 3 DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:48:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 INCORRECT 0 "P=.28*2MW" DEFINE-AREA USNA SP212 General Physics II 2 (= power_COLLECTOR_SUNLIGHT_1 (* (* 0.28 2) (DNUM 1 MW))) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:48:29.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 INCORRECT 0 "P=.28*2" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DEFINE-AREA USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (* 0.28 2)) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:48:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 2 DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:49:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:50:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:50:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:50:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:51:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-5 label="Pc";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 22 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:51:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:51:23.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:52:19.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT uniform-intensity-to-power Right indeed. If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:52:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 0 "I=P/A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 66 (= int_COLLECTOR_SUNLIGHT_1 (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:52:57.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 INCORRECT 1 "P" Unable to solve for P. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:55:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:55:34.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 1 ".28*P=Pc" GIVEN-FRACTION USNA SP212 General Physics II (= (* 0.28 power_COLLECTOR_SUNLIGHT_1) power_ELECTRIC_OUTPUT_COLLECTOR_1) DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:55:46.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-46-10 2007-04-23 16:55:50.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476189 m^2" USNA SP212 General Physics II 98 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:56:56.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:57:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-3 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:41.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 5 INCORRECT System-4 label="sun";body=sunlight;time=NIL DRAW-BODY USNA SP212 General Physics II 19 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:43.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 6 INCORRECT System-4 label="sun";body=sunlight;time=NIL DRAW-BODY USNA SP212 General Physics II 18 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:44.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 7 HINT System-4 label=sun The closest matching CORRECT entry seems to be done already, so you really don't need to generate it again. If you want to anyway, click on Explain more. 1 DRAW-BODY USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:54.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 8 INCORRECT System-5 label="sun";body=sunlight;time=NIL DRAW-BODY USNA SP212 General Physics II 17 DDD63 DDD63-Apr23-15-56-09 2007-04-23 16:59:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:01:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:01:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:02:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 INCORRECT 0 "P=I/c" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:02:19.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT 0 What equation do you wish to write? 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:02:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:03:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:03:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 HINT You should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 11 HINT A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 12 HINT When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 13 HINT Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 12 DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:47.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 14 CORRECT Vector-8 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=128 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:04:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:09.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:38.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 INCORRECT 0 "F=1.3 kW/m^2" Units are inconsistent. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= Fp_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 6 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:05:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 7 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:06:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 8 CORRECT 0 "F= 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 20 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:06:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-AREA USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:06:09.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-AREA USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:06:18.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT uniform-intensity-to-power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AREA USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:07:12.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 HINT inst-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 DEFINE-AREA USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:07:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:07:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 7 CORRECT Var-9 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 21 DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 16 DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:47.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 35 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:52.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:08:56.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" PRESSURE-FORCE USNA SP212 General Physics II 52 DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:09:07.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 CORRECT 3 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 72 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:09:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DDD63 DDD63-Apr23-15-56-09 2007-04-23 17:09:13.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.095830769231 m^2" USNA SP212 General Physics II 83 DDDFF DDDFF-May06-23-44-15 2007-05-07 00:49:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DDDFF DDDFF-May06-23-44-15 2007-05-07 00:49:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DDDFF DDDFF-May06-23-44-15 2007-05-07 00:49:16.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= (/ ampE_WAVE ampM_WAVE) c) DDDFF DDDFF-May06-23-44-15 2007-05-07 00:49:20.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDDFF DDDFF-May06-23-44-15 2007-05-07 00:49:23.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DDDFF DDDFF-May06-23-52-09 2007-05-07 00:52:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DDDFF DDDFF-May06-23-52-09 2007-05-07 00:53:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=P;agent=NIL;time=T0;value="8km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DDDFF DDDFF-May06-23-52-09 2007-05-07 00:53:38.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-2 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:53:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:53:55.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 14 DDDFF DDDFF-May06-23-52-09 2007-05-07 00:53:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 INCORRECT Vector-4 label="d";type=Displacement;body=P;agent=NIL;time=T0;dir=0;mag=210 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 12 DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 HINT Try introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 6 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:54:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 7 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 8 DDDFF DDDFF-May06-23-52-09 2007-05-07 00:55:22.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 8 CORRECT Vector-5 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=227 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:55:28.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 18 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DDDFF DDDFF-May06-23-52-09 2007-05-07 00:56:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-6 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:57:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 62 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DDDFF DDDFF-May06-23-52-09 2007-05-07 00:57:48.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:58:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 3 "P" USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:58:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 3 CORRECT 4 "I" USNA SP212 General Physics II DDDFF DDDFF-May06-23-52-09 2007-05-07 00:58:10.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 93 DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 25 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:53.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=.28*I*A" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 GIVEN-FRACTION USNA SP212 General Physics II 50 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* 0.28 int_COLLECTOR_SUNLIGHT_1) A_COLLECTOR)) DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:53.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=.28*I*A" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 50 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* 0.28 int_COLLECTOR_SUNLIGHT_1) A_COLLECTOR)) DDDFF DDDFF-May06-23-58-46 2007-05-07 01:00:58.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 1 "A" USNA SP212 General Physics II DDDFF DDDFF-May06-23-58-46 2007-05-07 01:01:01.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476191 m^2" USNA SP212 General Physics II 81 DDDFF DDDFF-May07-00-01-46 2007-05-07 01:02:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DDDFF DDDFF-May07-00-01-46 2007-05-07 01:02:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:05:01.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 33 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DDDFF DDDFF-May07-00-01-46 2007-05-07 01:05:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:05:21.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 50 DDDFF DDDFF-May07-00-01-46 2007-05-07 01:05:50.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-3 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=63 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:21.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:25.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 69 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:29.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 INCORRECT 3 "A" Unable to solve for A. One thing you probably need is an equation specifying the given value of F. 1 1 USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 3 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 78 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:47.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DDDFF DDDFF-May07-00-01-46 2007-05-07 01:06:59.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.095830769231 m^2" USNA SP212 General Physics II 89 DDDFF DDDFF-May07-00-07-29 2007-05-07 01:10:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 CORRECT Var-1 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 16 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DDDFF DDDFF-May07-00-07-29 2007-05-07 01:10:32.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 CORRECT Var-2 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8m" DEFINE-DISTANCE USNA SP212 General Physics II 25 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DDDFF DDDFF-May07-00-07-29 2007-05-07 01:10:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DDDFF DDDFF-May07-00-07-29 2007-05-07 01:10:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s=s1+s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DDDFF DDDFF-May07-00-07-29 2007-05-07 01:11:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-4 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DDDFF DDDFF-May07-00-07-29 2007-05-07 01:11:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 1 "c=s/t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 69 (= c (/ dist_PULSE_13 t_13)) DDDFF DDDFF-May07-00-07-29 2007-05-07 01:11:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 1 "c=s/t" WRITE-SDD USNA SP212 General Physics II 69 (= c (/ dist_PULSE_13 t_13)) DDDFF DDDFF-May07-00-07-29 2007-05-07 01:11:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DDDFF DDDFF-May07-00-07-29 2007-05-07 01:11:13.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "t = 2.5617722511218077 s" USNA SP212 General Physics II 100 DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 2 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:20.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:48:44.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:12.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT energy-decay No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:17.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT pendulum-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:18.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 5 DEFINE-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:50:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 18 DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 INCORRECT 0 "c=3*10^8 m/s" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 17 (= c (* (* 3 (^ 10 8)) (DNUM 1 m/s))) DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:41.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 8 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 61 (= ampE_WAVE (* c ampM_WAVE)) DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:58:48.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDEEF DDEEF-Apr23-22-47-58 2007-04-23 23:59:00.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 92 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:15:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:15:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:17:48.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 INCORRECT System-1 label="m";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:17:52.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 HINT System-1 label=m What other bodies can you define? 1 DRAW-BODY USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:17:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 HINT Analyzing the pulse is more important for solving this problem. 2 DRAW-BODY USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:17:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 6 HINT Choose the pulse as the body. 3 3 DRAW-BODY USNA SP212 General Physics II -10 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:04.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 7 CORRECT System-1 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -7 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -12 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:22.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -11 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -1 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:18:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:19:07.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 2 HINT Try introducing a variable for the distance travelled by the pulse from T1 to T2. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:19:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -6 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:21:46.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s2 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -7 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:22:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 INCORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8*2 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -8 (= dist_PULSE_23 (* (* 3.84e+8 2) (DNUM 1 m))) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:22:20.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 HINT Var-4 label=s2 (3.84e+8 * 2) * (1 m) is not the correct value for s2. Reread the problem statement carefully to find the given value for s2, the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:22:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 HINT The correct value for s2 is 384000000 m. 2 2 DEFINE-DISTANCE USNA SP212 General Physics II -12 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:22:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 5 CORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="384000000m" DEFINE-DISTANCE USNA SP212 General Physics II -3 (= dist_PULSE_23 (DNUM 384000000 m)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:22:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:23:03.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:23:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:24:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 HINT wave-speed-refraction No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:24:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 5 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-DISTANCE USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:24:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 6 CORRECT Var-5 label="s3";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II -2 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:25:15.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 INCORRECT 0 "s3=c*t" Undefined variable: t 1 DEFINE-DURATION USNA SP212 General Physics II -3 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:25:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-6 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II -2 DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:25:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "s3=c*t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 41 (= dist_PULSE_13 (* c t_13)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:25:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "s3=c*t" WRITE-SDD USNA SP212 General Physics II 41 (= dist_PULSE_13 (* c t_13)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:25:51.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 INCORRECT 1 "23=s*s2" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DEFINE-SPEED USNA SP212 General Physics II (= 23 (* dist_PULSE_12 dist_PULSE_23)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-SPEED USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT Your goal should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-SPEED USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT You should be introducing a variable for the speed of the pulse. 3 DEFINE-SPEED USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 INCORRECT Var-7 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="c" The value of v is not given in this problem. It should be marked unknown. 1 1 DEFINE-SPEED USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 CORRECT Var-7 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:45.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:26:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 CORRECT 1 "s3=s+s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:27:04.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "s3" USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:27:41.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 CORRECT 3 "t" USNA SP212 General Physics II DDEEF DDEEF-Apr23-23-15-14 2007-04-24 00:27:54.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "t = 2.5617722511218077 s" USNA SP212 General Physics II 72 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:02:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:02:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:02:29.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:02:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:02:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:03:17.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:03:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:06:59.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 HINT Why don't you continue working on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:07:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:07:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 4 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II 11 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:07:54.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 9 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:08:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 19 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:08:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:19:29.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |collector| |T0| |electric_output| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:19:38.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |electric_output| |T0| |collector| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:19:46.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |sunlight| |T0| |collector| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. Let's just assume that you are seeking the area of the collector. 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:19:49.0 US/Eastern HINT_REQUEST Choose- HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 HINT "OK" What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 5 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:20:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 6 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:20:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 7 HINT max-transverse-abs-acceleration-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 7 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:20:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 8 HINT A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 8 DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 9 CORRECT Var-4 label="P1";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 DEFINE-AREA USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT A good step would be introducing a variable for the area of the collector. 2 DEFINE-AREA USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:21:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P1 = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 14 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:09.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P1=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 58 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:26.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P = 0.28 * P1 3 3 GIVEN-FRACTION USNA SP212 General Physics II 53 DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P=.28*P1" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:22:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "P1" USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:23:06.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 3 "A" USNA SP212 General Physics II DDEEF DDEEF-Apr24-03-01-55 2007-04-24 04:23:22.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476189 m^2" USNA SP212 General Physics II 84 DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:21:42.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 INCORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" The value of B is not given in this problem. It should be marked unknown. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:21:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 3 DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:22:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 (= ampE_WAVE (DNUM 120 V/m)) DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:22:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= (/ ampE_WAVE ampM_WAVE) c) DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:22:32.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DDF07 DDF07-Apr10-21-19-54 2007-04-10 22:22:35.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 98 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:25:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 1 INCORRECT Var-2 label="l";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8e3 m" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 3 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION TRANSMITTER P TIME 1) (DNUM 180 deg)) 2 INCORRECT Var-2 label="l";quant=length;subtype=NIL;body=P;agent=NIL;time=NIL;value="8e3 m" DRAW-OPPOSITE-RELATIVE-POSITION USNA SP212 General Physics II 2 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:08.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT Var-2 label=l This problem should be solved by drawing relative position vectors. Although the length you've defined might have the same value as the magnitude of a relative position, it is an Andes convention to use quantities that appear in the principles whenever possible. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=232 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 3 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:32.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8e3 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 13 (= r_P_TRANSMITTER_1 (DNUM 8000.0 m)) DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:26:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280e3 W" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 23 (= power_TRANSMITTER_1 (DNUM 280000.0 W)) DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:28:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 INCORRECT 1 "I=P/($p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 22 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* $P (^ r_P_TRANSMITTER_1 2)))) DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:28:06.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 What equation do you wish to write? 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:29:03.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT spherical-intensity-to-power Equations of that type appear within the problem solution. You should write the equation in the form P = 4*$p*r^2*I using your own variables. If you do not want to write this equation and are not sure what to do, why don't you call Light-Bulb-Help. 2 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 17 DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:29:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 CORRECT 1 "P=4*$p*r^2*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 61 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:29:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DDF07 DDF07-Apr10-21-24-56 2007-04-10 22:29:33.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 93 DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:31:30.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3e3 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1300.0 W/m^2)) DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:31:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:33:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT 0 "P=I/c" DRAW-BODY USNA SP212 General Physics II 12 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:34:05.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 INCORRECT 0 "P=I/c" DRAW-BODY USNA SP212 General Physics II 11 (= Pr_SAIL (/ int_SAIL_SUNLIGHT_1 c)) DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:34:07.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT 0 What equation do you wish to write? 1 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:34:57.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 INCORRECT 0 "I=S" Undefined variable: S 1 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:35:23.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 5 HINT 0 Undefined variable: S 1 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:35:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 6 HINT Variables must be defined before being used in an equation. Vectors are defined by the drawing tools (the buttons along the left edge of the window) and scalars are defined by the clicking on the 'Variable' button at the top of the window.\n If all variables have been defined, the problem may be incorrect unit symbols, including case errors. For example, 'N', not 'n', is the symbol for Newtons. 2 2 DRAW-BODY USNA SP212 General Physics II 6 DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:00.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 7 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:30.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 8 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-BODY USNA SP212 General Physics II 5 DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 9 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 10 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:48.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 11 CORRECT System-4 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:37:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:38:39.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:38:42.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DEFINE-PRESSURE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:38:52.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:39:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:39:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:39:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:39:48.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=0;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:40:06.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=90;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 11 DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:40:13.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=270;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:40:18.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 INCORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=180;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:40:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=58 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DDF07 DDF07-Apr10-21-30-39 2007-04-10 22:40:33.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 Unknown 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:20:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DE099 DE099-Apr12-09-19-43 2007-04-12 10:20:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:20:44.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:12.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT electromagnetic-wave-field-amplitude Right indeed. A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=B*c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= ampE_WAVE (* ampM_WAVE c)) DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:33.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:38.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 INCORRECT Answer-1 "4 T" USNA SP212 General Physics II DE099 DE099-Apr12-09-19-43 2007-04-12 10:21:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 2 CORRECT Answer-1 "4e-7 T" USNA SP212 General Physics II 97 DE099 DE099-Apr12-09-22-22 2007-04-12 10:22:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE099 DE099-Apr12-09-22-22 2007-04-12 10:23:12.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-2 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=231 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:23:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 25 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:17.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:30.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:24:54.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 5 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 20 DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-5 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:50.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:25:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:26:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 15 DE099 DE099-Apr12-09-22-22 2007-04-12 10:26:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 59 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DE099 DE099-Apr12-09-22-22 2007-04-12 10:26:33.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DE099 DE099-Apr12-09-22-22 2007-04-12 10:26:36.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 90 DE099 DE099-Apr12-09-26-52 2007-04-12 10:28:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE099 DE099-Apr12-09-26-52 2007-04-12 10:28:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:28:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II 14 DE099 DE099-Apr12-09-26-52 2007-04-12 10:28:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 INCORRECT Var-4 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2.0 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DE099 DE099-Apr12-09-26-52 2007-04-12 10:28:56.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT Var-4 label=P I cannot determine what's wrong with this entry. Try getting suggestions for a correct next step by clicking on the light bulb button or 'Explain further.' 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:11.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-6 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 13 DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:15.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 6 INCORRECT Axes-6 body=NIL;dir=64;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:25.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 7 CORRECT Axes-6 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 13 DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 23 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:29:50.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:30:56.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-7 label="P2";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:16.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 0 "P=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:30.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 0 "P2=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 66 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:48.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 1 "P=0.28*P2" GIVEN-FRACTION USNA SP212 General Physics II 67 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:52.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DE099 DE099-Apr12-09-26-52 2007-04-12 10:31:55.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 98 DE099 DE099-Apr12-09-33-03 2007-04-12 10:33:08.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 HINT Axes-1 label=NIL Although it is always okay to draw a coordinate system, none are needed for this problem. Click on the light bulb button or 'explain further' for suggestions on how to solve the problem without drawing axes. 1 DEFINE-INTENSITY USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:33:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE099 DE099-Apr12-09-33-03 2007-04-12 10:34:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-3 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:34:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:34:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DE099 DE099-Apr12-09-33-03 2007-04-12 10:34:35.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-4 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DE099 DE099-Apr12-09-33-03 2007-04-12 10:34:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:28.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 INCORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=180;mag=146 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 19 DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=146 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 27 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:35:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:36:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:36:42.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT intensity-to-poynting-vector-magnitude You have already tried that principle application. As I told you then it is wrong. In order to move ahead you need to try something that you have not tried before. Why don't you do that now. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:36:58.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT spherical-intensity-to-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:19.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:20.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 9 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 22 DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:36.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 10 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 42 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:40.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:43.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 59 DE099 DE099-Apr12-09-33-03 2007-04-12 10:37:53.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 INCORRECT 3 "P=F*A" Undefined variable: A 1 DEFINE-AREA USNA SP212 General Physics II 58 DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:03.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 INCORRECT 3 "P=F*A" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II (= Pr_SAIL (* Fp_SAIL_SUNLIGHT_1 A_SAIL)) DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 53 DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 3 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 72 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:43.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DE099 DE099-Apr12-09-33-03 2007-04-12 10:38:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 83 DE099 DE099-Apr12-09-39-03 2007-04-12 10:39:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:39:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DE099 DE099-Apr12-09-39-03 2007-04-12 10:39:45.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-1 label="pulse";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II 1 DE099 DE099-Apr12-09-39-03 2007-04-12 10:39:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:39:58.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:40:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:40:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:40:40.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-3 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 11 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:40:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:41:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-4 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 20 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:41:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 CORRECT Var-3 label="sq";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:41:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 5 CORRECT Var-3 label="s1";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:41:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:41:35.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:42:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:42:45.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:42:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT A good step would be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 CORRECT Var-5 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 CORRECT Var-6 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:40.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "s1+s2=v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 45 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:40.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "s1+s2=v*t" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 45 (= (+ dist_PULSE_12 dist_PULSE_23) (* sp_PULSE_13 t_13)) DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT It is good practice to identify the fundamental principles you are using by writing them purely symbolically in standard form before combining them with other equations or given values. Select "Review Physics Equations" on the Help Menu to view a list of principles and their standard forms. 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:43:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT A good solution would include distance = average speed * time, written as a separate equation. 3 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:44:03.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 INCORRECT 1 "distance=average speed*time" Syntax error in distance=average speed*time 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 44 ? DE099 DE099-Apr12-09-39-03 2007-04-12 10:44:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:44:33.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DE099 DE099-Apr12-09-39-03 2007-04-12 10:44:36.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DE099 DE099-Apr12-09-39-03 2007-04-12 10:44:40.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 75 DE099 DE099-May07-17-54-20 2007-05-07 18:55:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=146 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 84 DE099 DE099-May07-17-54-20 2007-05-07 18:57:01.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-4 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II DE099 DE099-May07-17-54-20 2007-05-07 18:57:15.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 5 CORRECT System-4 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II DE099 DE099-May07-17-54-20 2007-05-07 18:57:29.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=146 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:43:19.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 INCORRECT Answer-1 "120 T" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:43:21.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 2 INCORRECT Answer-1 "120 V" Units are inconsistent. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:44:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 3 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:44:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 4 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:44:45.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:44:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DE147 DE147-Apr25-20-04-00 2007-04-25 21:45:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DE147 DE147-Apr25-20-04-00 2007-04-25 21:45:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= (/ ampE_WAVE ampM_WAVE) c) DE147 DE147-Apr25-20-04-00 2007-04-25 21:45:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE147 DE147-Apr25-20-04-00 2007-04-25 21:45:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 94 DE147 DE147-Apr25-20-45-57 2007-04-25 21:46:48.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:47:02.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 INCORRECT Var-2 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:47:23.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-4 label="E";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:47:29.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 INCORRECT System-5 label="M";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:47:55.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 INCORRECT Vector-7 label="r";type=Position;body=moon;agent=earth;time=T0 to T2;dir=0;mag=249 DEFINE-DURATION USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:48:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-8 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 1 DE147 DE147-Apr25-20-45-57 2007-04-25 21:48:35.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT 0 "c*t=2*3.48e8" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II (= (* c t_13) (* 2 3.48e+8)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:48:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 INCORRECT 0 "c*t=2*3.48e8 m" DEFINE-DISTANCE USNA SP212 General Physics II (= (* c t_13) (* (* 2 3.48e+8) (DNUM 1 m))) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:02.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-9 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 11 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 CORRECT 0 "c*t=2*s" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 43 (= (* c t_13) (* 2 dist_PULSE_12)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 CORRECT 0 "c*t=2*s" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 43 (= (* c t_13) (* 2 dist_PULSE_12)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 0 "c*t=2*s" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 43 (= (* c t_13) (* 2 dist_PULSE_12)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "c*t=2*s" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 43 (= (* c t_13) (* 2 dist_PULSE_12)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "c*t=2*s" Although equation 1 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-SDD USNA SP212 General Physics II 43 (= (* c t_13) (* 2 dist_PULSE_12)) DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 HINT It is good practice to identify the fundamental principles you are using by writing them purely symbolically in standard form before combining them with other equations or given values. Select "Review Physics Equations" on the Help Menu to view a list of principles and their standard forms. 2 USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 HINT A good solution would include distance = average speed * time, written as a separate equation. 3 3 USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:20.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 CORRECT 1 "t" USNA SP212 General Physics II DE147 DE147-Apr25-20-45-57 2007-04-25 21:49:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 74 DE147 DE147-Apr25-20-49-48 2007-04-25 21:50:31.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE147 DE147-Apr25-20-49-48 2007-04-25 21:50:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 12 DE147 DE147-Apr25-20-49-48 2007-04-25 21:50:48.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 14 DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:25.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=228 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 0 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 58 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:31.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 INCORRECT 1 "I" Unable to solve for I. One thing you probably need is an equation specifying the given value of r. 1 1 USNA SP212 General Physics II DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 1 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 68 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:47.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "I" USNA SP212 General Physics II DE147 DE147-Apr25-20-49-48 2007-04-25 21:51:53.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 99 DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=electric_output;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 12 DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=all forces;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 11 DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:44.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=all forces;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:45.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Var-3 label=P Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 21:56:59.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 INCORRECT Var-3 label="P";quant=power;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 21:57:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 6 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 21:59:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 12 DE147 DE147-Apr25-20-52-09 2007-04-25 21:59:38.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 0 "P=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 56 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE147 DE147-Apr25-20-52-09 2007-04-25 21:59:42.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 INCORRECT 1 "P" Unable to solve for P. One thing you probably need is an equation specifying the given value of the power supplied to the electric_output from the collector at T0. 1 1 USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 21:59:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 INCORRECT 1 "P=2MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (DNUM 2 MW)) DE147 DE147-Apr25-20-52-09 2007-04-25 22:00:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 2 INCORRECT 1 "P=2 MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= power_COLLECTOR_SUNLIGHT_1 (DNUM 2 MW)) DE147 DE147-Apr25-20-52-09 2007-04-25 22:00:06.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 3 HINT 1 2 MW is not the correct value for P, the power supplied to the collector from the sunlight at T0. It will usually be easier to leave the symbol P in your solution equations and let Andes do all calculations. Use the 'Solve For' command to compute the final answer when you have entered enough equations to determine it. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 51 DE147 DE147-Apr25-20-52-09 2007-04-25 22:00:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 4 INCORRECT 1 "P=2*.28 MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 50 (= power_COLLECTOR_SUNLIGHT_1 (* (* 2 0.28) (DNUM 1 MW))) DE147 DE147-Apr25-20-52-09 2007-04-25 22:01:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 5 CORRECT 1 "P*.28=2 MW" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 57 (= (* power_COLLECTOR_SUNLIGHT_1 0.28) (DNUM 2 MW)) DE147 DE147-Apr25-20-52-09 2007-04-25 22:01:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 "P*.28=2 MW" GIVEN-FRACTION USNA SP212 General Physics II 57 (= (* power_COLLECTOR_SUNLIGHT_1 0.28) (DNUM 2 MW)) DE147 DE147-Apr25-20-52-09 2007-04-25 22:01:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DE147 DE147-Apr25-20-52-09 2007-04-25 22:01:23.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 88 DE147 DE147-Apr25-21-01-40 2007-04-25 22:02:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE147 DE147-Apr25-21-01-40 2007-04-25 22:03:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE147 DE147-Apr25-21-01-40 2007-04-25 22:03:11.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 0 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 33 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE147 DE147-Apr25-21-01-40 2007-04-25 22:03:14.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 1 "P" USNA SP212 General Physics II DE147 DE147-Apr25-21-01-40 2007-04-25 22:03:20.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 50 DE147 DE147-Apr25-21-01-40 2007-04-25 22:04:51.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-3 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=83 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:01.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 CORRECT System-4 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 61 DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 2 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 69 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:33.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:43.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 INCORRECT 3 "F/A=@*I/c" Syntax error in F/A= *I/c 1 PRESSURE-FORCE USNA SP212 General Physics II ? DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 CORRECT 3 "F/A=2*I/c" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 PRESSURE-FORCE USNA SP212 General Physics II 80 (= (/ Fp_SAIL_SUNLIGHT_1 A_SAIL) (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:49.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 CORRECT 3 "F/A=2*I/c" Although equation 4 is correct, you have not displayed a fundamental principle being used in symbolic form all by itself. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 80 (= (/ Fp_SAIL_SUNLIGHT_1 A_SAIL) (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE147 DE147-Apr25-21-01-40 2007-04-25 22:05:54.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 4 "A" USNA SP212 General Physics II DE147 DE147-Apr25-21-01-40 2007-04-25 22:06:00.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 91 DE14D DE14D-Mar26-20-22-52 2007-03-26 21:22:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:22:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:22:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 3 3 DEFINE-AMPLITUDE USNA SP212 General Physics II -5 DE14D DE14D-Mar26-20-22-52 2007-03-26 21:23:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 20 (= ampE_WAVE (DNUM 120 V/m)) DE14D DE14D-Mar26-20-22-52 2007-03-26 21:23:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:23:38.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 2 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:23:45.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 3 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:14.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 4 HINT wavenumber-lambda-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:16.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 5 HINT frequency-of-wave No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 6 HINT A good step would be introducing a variable for the amplitude of the magnetic field in the wave. 5 DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 7 HINT Define a variable for the amplitude of the magnetic field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 6 6 DEFINE-AMPLITUDE USNA SP212 General Physics II 15 DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 8 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Why don't you continue working on applying the formula for maximum speed of an oscillation. 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT Write the equation E = c * B. 3 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 10 DE14D DE14D-Mar26-20-22-52 2007-03-26 21:24:40.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 54 (= ampE_WAVE (* c ampM_WAVE)) DE14D DE14D-Mar26-20-22-52 2007-03-26 21:25:11.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE14D DE14D-Mar26-20-22-52 2007-03-26 21:25:17.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 85 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:22.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is a good idea to begin most problems by drawing an axis. This helps to ground your work and will be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:30.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 CORRECT Axes-1 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 6 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:31.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 2 HINT why don't you start with entering the given value of the total power produced by the transmitter at T0. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 3 HINT Your goal should be introducing a variable for the total power produced by the transmitter at T0. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (DNUM 280 kW))) 4 HINT Define a variable for the total power produced by the transmitter at T0 by using the Add Variable command on the Variable menu and selecting power. 4 4 DEFINE-NET-POWER-OUT USNA SP212 General Physics II 1 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:50.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="" The value of P can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -2 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:44:59.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 INCORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 k" Syntax error in P=280 k 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II -3 ? DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 8 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT A good step would be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 2 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:28.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 INCORRECT Vector-3 label="r";type=Position;body=transmitter;agent=P;time=T0;dir=0;mag=75 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:32.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 6 HINT Vector-3 label=r The relative position you defined will point FROM P TO the transmitter. Is that the direction you want? 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 7 HINT For this problem you need to use the relative position of P with respect to the transmitter, instead of the other way around. 2 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II -3 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:41.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 8 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=75 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 HINT You can find the value of the magnitude of the relative position of P with respect to the transmitter in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 3 HINT The value of the magnitude of the relative position of P with respect to the transmitter is given as 8.0 km. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 4 HINT Enter the equation r = 8.0 km. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -8 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:45:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 5 CORRECT 0 "r=8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 2 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DE14D DE14D-Mar26-20-44-16 2007-03-26 21:49:23.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:49:42.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |all sources| NIL "") 'NIL) That quantity is not mentioned in the Andes solution. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:49:52.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 3 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:07.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 4 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:08.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT spring-mass-oscillation No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 5 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT A good step would be introducing a variable for the intensity supplied to P at T0 due to the transmitter. 6 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:10.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 7 7 DEFINE-INTENSITY USNA SP212 General Physics II -3 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:23.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 8 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II -2 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -7 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:40.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-5 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II -12 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:52.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-6 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:50:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II -17 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:24.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 27 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:25.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 22 DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:29.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 2 CORRECT 2 "P" USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:35.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 INCORRECT Answer-1 "280000 W" Units are inconsistent. 1 1 USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:45.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 3 CORRECT 3 "I" USNA SP212 General Physics II DE14D DE14D-Mar26-20-44-16 2007-03-26 21:51:52.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 2 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 50 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:00:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="2.0 MW" The value of P is not given in this problem. It should be marked unknown. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:01:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 3 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:01:18.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:01:30.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 4 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:01:32.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:02:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 2 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:02:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 3 HINT Your goal should be introducing a variable for the intensity supplied to the collector at T0 due to the sunlight. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:02:26.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2))) 4 HINT Define a variable for the intensity supplied to the collector at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II -1 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:02:43.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -2 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:02:49.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT Var-3 label=I The value of I can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 DEFINE-INTENSITY USNA SP212 General Physics II -7 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:06.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 INCORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 w/M^2" Syntax error in I=960 w/M^2 1 DEFINE-INTENSITY USNA SP212 General Physics II ? DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:08.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 HINT The equation or the units in it are not in a recognizable form. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 HINT Though I can't tell exactly what the mistake is, a few common sources of errors are: (a) Unit symbols are case sensitive. (b) Multiplication always requires an explicit multiplication sign: W=m*g, NOT W=mg. (c) Units attach only to numbers, not to variables or expressions. 3 3 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:14.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 6 HINT Var-3 label=I Syntax error in I=960 w/M^2 1 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 7 HINT The equation or the units in it are not in a recognizable form. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:03:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 8 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 2 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 HINT A good step would be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II -3 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 CORRECT Var-4 label="P2";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 7 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:27.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:04:50.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Yes. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:00.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT electric-power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:10.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 HINT wave-speed-light No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 5 HINT Try introducing a variable for the area of the collector. 5 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 6 HINT Define a variable for the area of the collector by using the Add Variable command on the Variable menu and selecting Area. 6 6 DEFINE-AREA USNA SP212 General Physics II 2 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:20.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 7 CORRECT Var-5 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 3 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:21.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:23.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation P = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II -2 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:39.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "P=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 42 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation P2 = 0.28 * P 3 3 GIVEN-FRACTION USNA SP212 General Physics II 37 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:53.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "P2=0.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE14D DE14D-Mar28-18-59-41 2007-03-28 20:05:55.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 32 DE14D DE14D-Mar28-18-59-41 2007-03-28 20:06:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DE14D DE14D-Mar28-18-59-41 2007-03-28 20:06:08.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 63 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:09:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:09:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:00.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-1 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 12 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:02.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 HINT why don't you start with entering the given value of the intensity supplied to the sail at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 3 HINT Try introducing a variable for the intensity supplied to the sail at T0 due to the sunlight. 3 DEFINE-INTENSITY USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 4 HINT Define a variable for the intensity supplied to the sail at T0 due to the sunlight by using the Add Variable command on the Variable menu and selecting intensity. 4 4 DEFINE-INTENSITY USNA SP212 General Physics II 7 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 5 CORRECT Var-2 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 15 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:30.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:10:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 10 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:11:42.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:11:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT Vector-5 label=F Your goal should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:11:44.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:11:45.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:11:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 5 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:00.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 11 INCORRECT Vector-3 label="p";type=Momentum;body=sail;agent=NIL;time=T0;dir=NIL;mag=72 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 3 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:02.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 12 HINT Vector-3 label=p None of the solutions that I know include a momentum vector. Try clicking on the light bulb button or 'explain further' for suggestions about another approach. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 13 HINT 0 Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 14 HINT 0 You should be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 15 HINT 0 A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 16 HINT 0 When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 17 HINT 0 Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II -2 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:12:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 18 CORRECT Vector-4 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=69 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II -1 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:16.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -6 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:23.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F= 20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 2 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:36.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:57.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 3 HINT period-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:13:58.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 4 HINT doppler-frequency No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 5 HINT Try introducing a variable for the pressure at the sail at T0. 5 DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 6 HINT Define a variable for the pressure at the sail at T0 by using the Add Variable command on the Variable menu and selecting Pressure. 6 6 DEFINE-PRESSURE USNA SP212 General Physics II -3 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 7 CORRECT Var-5 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Why don't you continue working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT the sunlight reflects off the sail. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Write the equation P = (2 * I) / c 4 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II -8 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:14:29.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 12 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 HINT You should be introducing a variable for the area of the sail. 2 DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 HINT Define a variable for the area of the sail by using the Add Variable command on the Variable menu and selecting Area. 3 3 DEFINE-AREA USNA SP212 General Physics II 7 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:34.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 4 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:36.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 2 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:43.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 22 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For ...' to find a value for each of the sought quantities (if you have not already) and then enter those values in the answer boxes. 1 1 USNA SP212 General Physics II 17 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:50.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT 3 "P" USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:56.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT Answer-1 "8.672666475151953e-6 Pa" USNA SP212 General Physics II 33 DE14D DE14D-Mar28-19-09-35 2007-03-28 20:15:59.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT 4 "A" USNA SP212 General Physics II DE14D DE14D-Mar28-19-09-35 2007-03-28 20:16:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 44 DE16B DE16B-Apr23-19-12-00 2007-04-23 21:46:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT It is a good idea to begin any problem by enumerating the given quantities. Why don't you start by doing that now. Why don't you work on entering the given value of the amplitude of the electric field in the wave. 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE16B DE16B-Apr23-19-12-00 2007-04-23 21:47:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DE16B DE16B-Apr23-19-12-00 2007-04-23 21:47:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II DE16B DE16B-Apr23-19-12-00 2007-04-23 21:48:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E/B=c" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 69 (= (/ ampE_WAVE ampM_WAVE) c) DE16B DE16B-Apr23-19-12-00 2007-04-23 21:50:00.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE16B DE16B-Apr23-19-12-00 2007-04-23 21:50:04.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "B = 4.0027691423778244e-7 T" USNA SP212 General Physics II 100 DE16B DE16B-Apr23-20-50-46 2007-04-23 21:51:27.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 6 DE16B DE16B-Apr23-20-50-46 2007-04-23 21:51:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE16B DE16B-Apr23-20-50-46 2007-04-23 21:53:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II 14 DE16B DE16B-Apr23-20-50-46 2007-04-23 21:54:01.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-3 label=s Although you can always define a distance variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:54:07.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:54:26.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:54:43.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 5 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:57:02.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 INCORRECT 0 "I=P/(4*$p*8000)" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) 8000))) DE16B DE16B-Apr23-20-50-46 2007-04-23 21:57:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 3 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DEFINE-NET-POWER-OUT USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:25.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 4 INCORRECT Var-6 label="P1";quant=net-power-out;subtype=NIL;body=P;agent=NIL;time=T0;value="" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 13 DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT Why don't you continue working on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 HINT Your goal should be introducing a variable for the magnitude of the relative position of P with respect to the transmitter. 2 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 3 HINT You know the direction of the position of P relative to the transmitter. 3 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 4 HINT Use the relative position drawing tool (labeled R) to draw the position of P with respect to the transmitter at T0 at 0 degrees. 4 4 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 8 DE16B DE16B-Apr23-20-50-46 2007-04-23 21:58:56.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 5 CORRECT Vector-7 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=221 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:59:01.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 INCORRECT 0 "I=P/(4*$p*r)" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) r_P_TRANSMITTER_1))) DE16B DE16B-Apr23-20-50-46 2007-04-23 21:59:20.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 CORRECT 1 "r=8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 18 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DE16B DE16B-Apr23-20-50-46 2007-04-23 21:59:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 0 "I=P/(4*$p*r^2)" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 61 (= int_P_TRANSMITTER_1 (/ power_TRANSMITTER_1 (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)))) DE16B DE16B-Apr23-20-50-46 2007-04-23 21:59:41.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DE16B DE16B-Apr23-20-50-46 2007-04-23 21:59:45.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "I = 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 93 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:01:39.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II 6 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:02:18.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT 0 "P=2 MW" DRAW-UNROTATED-AXES USNA SP212 General Physics II 3 (= power_COLLECTOR_SUNLIGHT_1 (DNUM 2 MW)) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:02:22.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT 0 2 MW is not the correct value for P, the power supplied to the collector from the sunlight at T0. It will usually be easier to leave the symbol P in your solution equations and let Andes do all calculations. Use the 'Solve For' command to compute the final answer when you have entered enough equations to determine it. 1 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:02:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 INCORRECT Var-2 label="P1";quant=power;subtype=NIL;body=electric_output;agent=all forces;time=T0;value="" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:02:52.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT Var-2 label=P1 Although you can always define a net-power variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:02:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:03:08.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 6 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -2 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:03:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:03:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 2 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-INTENSITY USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:03:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 3 HINT why don't you start with entering the given value of the intensity supplied to the collector at T0 due to the sunlight. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:04:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 4 INCORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=collector;agent=all sources;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II -3 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:04:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 7 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:05:24.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the power supplied to the electric_output from the collector at T0. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:05:56.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-5 label="Pc";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="" The value of Pc can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:06:25.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 INCORRECT Var-5 label="Pc";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="960*.28 W/m^2" The units in this equation are not consistent. If this is a symbolic equation, there is probably an error: check all your terms. Another possibility is that a number has been used without correct associated units. 1 1 DEFINE-POWER-VAR USNA SP212 General Physics II 6 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* (* 960 0.28) (DNUM 1 W/m^2))) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:06:43.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 3 INCORRECT 0 "960*.28" Syntax error in 960*.28 1 DEFINE-POWER-VAR USNA SP212 General Physics II ? DE16B DE16B-Apr23-21-00-22 2007-04-23 22:06:54.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 4 INCORRECT 0 "960*.28=" Syntax error in 960*.28= 1 DEFINE-POWER-VAR USNA SP212 General Physics II ? DE16B DE16B-Apr23-21-00-22 2007-04-23 22:07:01.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 5 HINT Why don't you continue working on entering the given value of the power supplied to the electric_output from the collector at T0. 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:07:03.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 6 HINT Your goal should be introducing a variable for the power supplied to the electric_output from the collector at T0. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:07:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 7 HINT Define a variable for the power supplied to the electric_output from the collector at T0 by using the Add Variable command on the Variable menu and selecting power 3 3 DEFINE-POWER-VAR USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:07:29.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 8 CORRECT Var-5 label="Pc";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 16 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:07:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:08:03.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:08:44.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 3 HINT max-transverse-speed-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:09:23.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 4 HINT straight-wire-bfield No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (uniform intensity). 4 DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:09:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 5 HINT A good step would be introducing a variable for the area of the collector. 5 DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:09:45.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 6 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:09:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:09:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:10:17.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 0 "I=P/A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 60 (= int_COLLECTOR_SUNLIGHT_1 (/ power_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:11:17.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 HINT 0 Why don't you continue with the solution by working on one quantity as given fraction of another. 1 GIVEN-FRACTION USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:11:27.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 HINT 0 You can determine the power supplied to the electric_output from the collector at T0 as a fraction of the power supplied to the collector from the sunlight at T0 from the problem statement 2 GIVEN-FRACTION USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:11:33.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 HINT 0 Write the equation Pc = 0.28 * P 3 3 GIVEN-FRACTION USNA SP212 General Physics II 55 DE16B DE16B-Apr23-21-00-22 2007-04-23 22:11:46.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 4 CORRECT 1 "Pc=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE16B DE16B-Apr23-21-00-22 2007-04-23 22:12:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DE16B DE16B-Apr23-21-00-22 2007-04-23 22:12:08.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "A = 7440.476190476189 m^2" USNA SP212 General Physics II 86 DE16B DE16B-Apr23-21-12-57 2007-04-23 22:38:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE16B DE16B-Apr23-21-12-57 2007-04-23 22:42:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:42:24.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DE16B DE16B-Apr23-21-12-57 2007-04-23 22:42:42.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 CORRECT System-2 label="b";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 20 DE16B DE16B-Apr23-21-12-57 2007-04-23 22:43:40.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DEFINE-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:44:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 2 CORRECT Var-3 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:44:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-4 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:45:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:46:00.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:46:37.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:47:41.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 INCORRECT 0 "P=2*A/c" Units are inconsistent. 1 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 19 (= Pr_SAIL (/ (* 2 A_SAIL) c)) DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:05.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 INCORRECT 0 "I=P/A" Units are inconsistent. 1 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 18 (= int_SAIL_SUNLIGHT_1 (/ Pr_SAIL A_SAIL)) DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 HINT Vector-5 label=F Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 7 HINT Vector-5 label=F A good step would be introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 8 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 9 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:48:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 10 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:49:34.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 11 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=115 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:49:57.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:50:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:50:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:50:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 13 DE16B DE16B-Apr23-21-12-57 2007-04-23 22:50:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 21 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE16B DE16B-Apr23-21-12-57 2007-04-23 22:51:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:51:19.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) That's right. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 22:51:53.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT radiation-pressure Right indeed. the sunlight reflects off the sail. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:36:12.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT Why don't you continue with the solution by working on finding the radiation pressure on the sail due to the sunlight. 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:36:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 CORRECT 1 "P=2*I/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 41 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE16B DE16B-Apr23-21-12-57 2007-04-23 23:37:05.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 INCORRECT 2 "I=P/A" Units are inconsistent. 1 1 PRESSURE-FORCE USNA SP212 General Physics II (= int_SAIL_SUNLIGHT_1 (/ Pr_SAIL A_SAIL)) DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 4 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 60 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 3 "P" USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:34.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT Answer-1 "P = 8.672666475151953e-6 Pa" USNA SP212 General Physics II 77 DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:43.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DE16B DE16B-Apr23-21-12-57 2007-04-23 23:39:47.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "A = 2306.095830769231 m^2" USNA SP212 General Physics II 88 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:43:36.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:43:42.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 INCORRECT System-1 label="m";body=moon;time=NIL DRAW-BODY USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:45:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:45:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -5 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:45:25.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 5 CORRECT System-2 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -3 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:46:28.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 INCORRECT Vector-3 label="r";type=Position;body=earth;agent=moon;time=T0;dir=NIL;mag=112 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:46:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 INCORRECT Vector-3 label="r";type=Position;body=earth;agent=moon;time=T0 to T2;dir=NIL;mag=112 DRAW-UNROTATED-AXES USNA SP212 General Physics II -4 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:46:39.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 HINT Vector-3 label=r None of the solutions that I know include a relative position vector. Try clicking on the light bulb button or 'explain further' for suggestions about another approach. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:46:47.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 4 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:47:02.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 5 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -3 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:47:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:47:17.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:47:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-5 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 7 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE16B DE16B-Apr23-22-41-33 2007-04-23 23:47:52.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:49:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 CORRECT Var-6 label="s2";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 17 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DE16B DE16B-Apr23-22-41-33 2007-04-23 23:49:19.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-DURATION USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:50:02.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Right indeed. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-DURATION USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:51:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-DURATION USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:51:43.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT wave-speed-light That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-DURATION USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:52:38.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:52:51.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 CORRECT Var-8 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II 18 DE16B DE16B-Apr23-22-41-33 2007-04-23 23:53:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 CORRECT Var-9 label="sc";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:53:37.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 1 "sc=s+s2" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DE16B DE16B-Apr23-22-41-33 2007-04-23 23:53:39.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "sc=v*t" WRITE-SDD USNA SP212 General Physics II 62 (= dist_PULSE_13 (* sp_PULSE_13 t_13)) DE16B DE16B-Apr23-22-41-33 2007-04-23 23:53:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 2 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DE16B DE16B-Apr23-22-41-33 2007-04-23 23:54:01.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 3 "t" USNA SP212 General Physics II DE16B DE16B-Apr23-22-41-33 2007-04-23 23:54:06.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "t = 2.5617722511218077 s" USNA SP212 General Physics II 93 DE18F DE18F-Apr24-19-02-28 2007-04-24 20:02:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DE18F DE18F-Apr24-19-02-28 2007-04-24 20:03:05.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 CORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 25 (= ampE_WAVE (DNUM 120 V/m)) DE18F DE18F-Apr24-19-02-28 2007-04-24 20:03:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:04:01.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:04:22.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT speed-of-wave No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:04:43.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT beat-frequency No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on applying the formula for maximum speed of an oscillation. 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:04:46.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 HINT Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 5 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:04:49.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 6 HINT Write the equation E = c * B. 6 6 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 20 DE18F DE18F-Apr24-19-02-28 2007-04-24 20:05:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 7 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 64 (= ampE_WAVE (* c ampM_WAVE)) DE18F DE18F-Apr24-19-02-28 2007-04-24 20:05:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 HINT You have completed all of the principle applications necessary to solve this problem. Right click in the first empty line in the equation pane and use 'Solve For...' to find a value for the sought quantity (if you have not already) and then enter that value in the answer box. 1 1 USNA SP212 General Physics II 59 DE18F DE18F-Apr24-19-02-28 2007-04-24 20:05:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 2 CORRECT 1 "B" USNA SP212 General Physics II DE18F DE18F-Apr24-19-02-28 2007-04-24 20:05:33.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 90 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:06:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DEFINE-NET-POWER-OUT USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:06:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 2 CORRECT Var-2 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 12 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE18F DE18F-Apr24-19-05-52 2007-04-24 20:06:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DRAW-UNROTATED-AXES USNA SP212 General Physics II 11 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:06:51.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Var-1 label=I Although you can always define a net-intensity variable, none are needed for any solution I know of this problem. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:07:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 INCORRECT Var-3 label="s";quant=distance;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="8 km" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:07:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 4 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:07:54.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 5 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 12 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:08:05.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 6 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:08:15.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the relative position of P with respect to the transmitter. 1 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:08:38.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 2 CORRECT Vector-6 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=193 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 13 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:08:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 23 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DE18F DE18F-Apr24-19-05-52 2007-04-24 20:08:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:06.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:29.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 4 HINT uniform-intensity-to-power No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on relating the intensity to power (spherical symmetry). 4 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:41.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 5 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:43.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 6 HINT Try introducing a variable for the intensity supplied to P at T0 due to the transmitter. 2 DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:09:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 7 HINT Define a variable for the intensity supplied to P at T0 due to the transmitter by using the Add Variable command on the Variable menu and selecting intensity. 3 3 DEFINE-INTENSITY USNA SP212 General Physics II 18 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 8 CORRECT Var-7 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Why don't you continue working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:09.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT You should use the body tool to draw a body choosing the transmitter as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 13 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:28.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 CORRECT System-8 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:39.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 CORRECT System-9 label="p";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:44.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:52.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:10:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 8 DE18F DE18F-Apr24-19-05-52 2007-04-24 20:11:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 52 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DE18F DE18F-Apr24-19-05-52 2007-04-24 20:11:28.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DE18F DE18F-Apr24-19-05-52 2007-04-24 20:11:36.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 "3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 83 DE18F DE18F-Apr24-19-12-04 2007-04-24 20:12:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:12:54.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 12 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:13:12.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 14 DE18F DE18F-Apr24-19-12-04 2007-04-24 20:13:35.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 23 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:13:44.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 INCORRECT 0 "P=I*A" DRAW-UNROTATED-AXES USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:13:49.0 US/Eastern HINT_REQUEST Whats-Wrong HINT_MSG Ask-Equation Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT 0 What equation do you wish to write? 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:13:55.0 US/Eastern HINT_REQUEST Choose-Equation HINT_MSG Whats-Wrong Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 HINT uniform-intensity-to-power Equations of that type appear within the problem solution. You should write the equation in the form P = I*A using your own variables. If you do not want to write this equation and are not sure what to do, why don't you call Light-Bulb-Help. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 18 DE18F DE18F-Apr24-19-12-04 2007-04-24 20:14:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 4 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:14:15.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 5 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:14:20.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:14:36.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:14:41.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:04.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 CORRECT Var-5 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P=.28*P" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_ELECTRIC_OUTPUT_COLLECTOR_1)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:39.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation Ps = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 13 DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:45.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "Ps=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 57 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:15:59.0 US/Eastern ATTEMPT Answer RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 INCORRECT Answer-1 "2000000 W" Units are inconsistent. 1 1 USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:16:16.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 2 CORRECT 2 "A" USNA SP212 General Physics II DE18F DE18F-Apr24-19-12-04 2007-04-24 20:16:27.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 2 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 85 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:17:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE18F DE18F-Apr24-19-16-47 2007-04-24 20:17:41.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:17:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-3 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:18:25.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 INCORRECT 0 "P=I*A" Units are inconsistent. 1 1 DRAW-BODY USNA SP212 General Physics II 12 (= Pr_SAIL (* int_SAIL_SUNLIGHT_1 A_SAIL)) DE18F DE18F-Apr24-19-16-47 2007-04-24 20:18:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:18:40.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 8 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:18:53.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-4 label="sail";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 19 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:18:56.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:19:01.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:19:39.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 CORRECT Vector-6 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=67 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:19:43.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:19:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:01.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 CORRECT 1 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 28 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:05.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:12.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:22.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:31.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT net-intensity No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 23 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:55.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 CORRECT 0 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 42 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE18F DE18F-Apr24-19-16-47 2007-04-24 20:20:58.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 HINT Why don't you continue with the solution by working on finding the pressure. 1 PRESSURE-FORCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:02.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 2 HINT Write the equation F = P * A 2 2 PRESSURE-FORCE USNA SP212 General Physics II 37 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:13.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 3 CORRECT 2 "F=P*A" PRESSURE-FORCE USNA SP212 General Physics II 57 (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL)) DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:19.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 3 "A" USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:26.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 73 DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:34.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "F" USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:41.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT 4 "P" USNA SP212 General Physics II DE18F DE18F-Apr24-19-16-47 2007-04-24 20:21:49.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-1 1 CORRECT Answer-1 " 8.672666475151953e-6 Pa" USNA SP212 General Physics II 84 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:22:54.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:00.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 INCORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 3 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 2 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -3 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:31.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 CORRECT System-2 label="pulse";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -2 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:48.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 CORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -1 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-DISTANCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 DEFINE-DISTANCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 DEFINE-DISTANCE USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:23:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -6 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:24:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 5 CORRECT Var-4 label="s01";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 4 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:24:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_23 (DNUM 3.84e+8 m))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:26:10.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 INCORRECT Var-5 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="" The value of s12 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:26:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 INCORRECT Var-5 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="1.92e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 2 (= dist_PULSE_23 (DNUM 1.92e+8 m)) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:27:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 CORRECT Var-5 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 12 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:27:14.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:27:36.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 2 HINT #.(wb-quant '(define-variable "t" |NIL| |duration| |NIL| |T0 to T2| |NIL| NIL "") 'NIL) Good! What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:27:54.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:15.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 4 HINT speed-equals-wave-speed That principle is part of a valid solution to this problem but you cannot use it as the first principle. Lets just assume that you will work on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 4 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:21.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 5 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 5 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:22.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 6 HINT You should be introducing a variable for the speed of the pulse. 6 DEFINE-SPEED USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:25.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 7 HINT Use the speed menu item under the Variables menu to define a variable for the speed of the pulse from T0 to T2. 7 7 DEFINE-SPEED USNA SP212 General Physics II 7 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:47.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (SPEED PULSE TIME (DURING 1 3))) 8 CORRECT Var-6 label="v";quant=speed;subtype=average;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-SPEED USNA SP212 General Physics II 8 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:51.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 DEFINE-DURATION USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 HINT You should be writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 DEFINE-DURATION USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 3 HINT Your goal should be introducing a variable for the duration of the interval from T0 to T2. 3 DEFINE-DURATION USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:28:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 4 HINT Use the variable definition tool (under 'variable' on the top menu bar) to define a variable for the duration of from T0 to T2. 4 4 DEFINE-DURATION USNA SP212 General Physics II 3 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:07.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 5 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 HINT Why don't you continue working on applying the "distance = average speed * time" principle with the pulse as the body from T0 to T2. 1 WRITE-SDD USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 2 HINT Try writing an equation involving the speed of the pulse from T0 to T2, and distance it travelled, and the duration of the trip. 2 WRITE-SDD USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 3 HINT Can you write an equation in terms of speed, distance travelled and duration? 3 WRITE-SDD USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 4 HINT You need to write an equation for the speed of the pulse from T0 to T2 in terms of the distance travelled by the pulse from T0 to T2 and the duration of the interval from T0 to T2. 4 WRITE-SDD USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:14.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 5 HINT The speed of an object is defined to be the distance traveled by the object divided by the duration of its trip. 5 WRITE-SDD USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:15.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 6 HINT Because v is the speed of the pulse from T0 to T2, and s is the distance travelled, and t is the duration of the trip, write v=s/t. 6 6 WRITE-SDD USNA SP212 General Physics II -2 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:26.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 7 CORRECT 0 "v=s/t" WRITE-SDD USNA SP212 General Physics II 42 (= sp_PULSE_13 (/ dist_PULSE_13 t_13)) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:29.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 HINT Why don't you continue with the solution by working on setting the speed to c. 1 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:34.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 2 HINT Light waves and radio waves have a special speed 2 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:35.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 3 HINT c is defined to be the speed of light. 3 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 4 HINT Write the equation v = c 4 4 WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 37 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 5 CORRECT 1 "v=c" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II (= sp_PULSE_13 c) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:48.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 INCORRECT 2 "t" Unable to solve for t. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 HINT Why don't you continue with the solution by working on calculating the sum of distances travelled by the pulse during from T0 to T2. 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:57.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 2 HINT Distances can be added together. 2 WRITE-SUM-DISTANCES USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:58.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 3 HINT The distance the pulse has travelled from T0 to T2 is equal to the sum of distances travelled during each sub-interval. 3 WRITE-SUM-DISTANCES USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:29:59.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 4 HINT Write the equation ?T02-VAR = s01 + s12. 4 4 WRITE-SUM-DISTANCES USNA SP212 General Physics II 32 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:30:31.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 5 INCORRECT 2 "?T02-VAR=s01+s02" Syntax error in T02-VAR=s01+s02 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II ? DE18F DE18F-Apr24-19-22-15 2007-04-24 20:30:37.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 6 INCORRECT 2 "T02-VAR=s01+s02" Undefined variables: (T02 VAR s02) 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II 31 DE18F DE18F-Apr24-19-22-15 2007-04-24 20:30:52.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 7 INCORRECT 2 "s=s01+s102" Undefined variable: s102 1 WRITE-SUM-DISTANCES USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:30:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 8 CORRECT 2 "s=s01+s12" WRITE-SUM-DISTANCES USNA SP212 General Physics II (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DE18F DE18F-Apr24-19-22-15 2007-04-24 20:30:57.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 2 3 "" USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:31:07.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 3 CORRECT 3 "t" USNA SP212 General Physics II DE18F DE18F-Apr24-19-22-15 2007-04-24 20:31:16.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 " 2.5617722511218077 s" USNA SP212 General Physics II 62 DE18F DE18F-Apr29-15-12-13 2007-04-29 16:12:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 4 CORRECT Var-1 label="s";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:32:22.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-1 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 6 DE20A DE20A-May06-23-31-37 2007-05-07 00:32:28.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 INCORRECT Var-2 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 3 DE20A DE20A-May06-23-31-37 2007-05-07 00:32:34.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 DEFINE-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:32:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 HINT why don't you start with entering the given value of the amplitude of the electric field in the wave. 2 DEFINE-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:32:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 3 HINT Your goal should be introducing a variable for the amplitude of the electric field in the wave. 3 DEFINE-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:32:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 4 HINT Define a variable for the amplitude of the electric field in the wave by using the Add Variable command on the Variable menu and selecting amplitude. 4 4 DEFINE-AMPLITUDE USNA SP212 General Physics II -2 DE20A DE20A-May06-23-31-37 2007-05-07 00:32:46.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 5 CORRECT Var-3 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 18 (= ampE_WAVE (DNUM 120 V/m)) DE20A DE20A-May06-23-31-37 2007-05-07 00:33:08.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:33:14.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 2 HINT #.(wb-quant '(define-variable "B" |NIL| |amplitude-magnetic| |wave| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:34:09.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 3 HINT electromagnetic-wave-field-amplitude Good! Find a formula the relation beteen the electric and magnetic fields in an electromagnetic wave. 3 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:34:11.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 4 HINT Write the equation E = c * B. 4 4 WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 13 DE20A DE20A-May06-23-31-37 2007-05-07 00:34:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 5 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 57 (= ampE_WAVE (* c ampM_WAVE)) DE20A DE20A-May06-23-31-37 2007-05-07 00:34:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE20A DE20A-May06-23-31-37 2007-05-07 00:34:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 88 DE20A DE20A-May06-23-34-45 2007-05-07 00:35:10.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=all sources;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:35:14.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II 3 DE20A DE20A-May06-23-34-45 2007-05-07 00:35:51.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=241 DRAW-RELATIVE-POSITION USNA SP212 General Physics II 4 DE20A DE20A-May06-23-34-45 2007-05-07 00:35:59.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 CORRECT 0 "r = 8.0 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 (= r_P_TRANSMITTER_1 (DNUM 8.0 km)) DE20A DE20A-May06-23-34-45 2007-05-07 00:36:15.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-4 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 24 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE20A DE20A-May06-23-34-45 2007-05-07 00:36:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:36:55.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 19 DE20A DE20A-May06-23-34-45 2007-05-07 00:37:01.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 3 CORRECT Axes-5 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:37:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:37:15.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 2 HINT #.(wb-quant '(define-variable "I" |NIL| |intensity| |P| |T0| |transmitter| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:37:40.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 3 HINT electric-power No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:05.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 4 HINT spherical-intensity-to-power Right indeed. It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 4 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 5 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 5 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:06.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 6 HINT You should use the body tool to draw a body choosing the transmitter as the body. 6 6 DRAW-BODY USNA SP212 General Physics II 14 DE20A DE20A-May06-23-34-45 2007-05-07 00:38:30.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY TRANSMITTER TIME NIL) 7 CORRECT System-6 label="t";body=transmitter;time=NIL DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:35.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (spherical symmetry). 1 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 2 HINT It is a good idea to begin by choosing the body or system of bodies you are going to focus on. 2 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:36.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 3 HINT First figure out which object you want to apply the principle to, and if necessary, what time or time interval to analyze. Then use the body tool (looks like a dot) to indicate your selections. 3 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 4 HINT You should use the body tool to draw a body choosing P as the body. 4 4 DRAW-BODY USNA SP212 General Physics II 9 DE20A DE20A-May06-23-34-45 2007-05-07 00:38:47.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (BODY P TIME NIL) 5 CORRECT System-7 label="P";body=P;time=NIL DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:49.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 HINT 1 Why don't you continue working on relating the intensity to power (spherical symmetry). 1 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:53.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 2 HINT 1 If the power goes out in all directions, the intensity at p is the power divided by the surface area of the sphere. 2 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 3 HINT 1 Imagine a sphere centered at the transmitter and extending to P; all of the power goes out through this sphere. 3 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:38:54.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 4 HINT 1 Write the equation P = 4 * $p * (r ^ 2) * I 4 4 WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 4 DE20A DE20A-May06-23-34-45 2007-05-07 00:39:08.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 5 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 48 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DE20A DE20A-May06-23-34-45 2007-05-07 00:39:12.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DE20A DE20A-May06-23-34-45 2007-05-07 00:39:17.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 " 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 79 DE20A DE20A-May06-23-40-23 2007-05-07 00:41:03.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 INCORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=sunlight;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:41:09.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 2 CORRECT Var-1 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2.0 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 12 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2.0 MW)) DE20A DE20A-May06-23-40-23 2007-05-07 00:41:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II 14 DE20A DE20A-May06-23-40-23 2007-05-07 00:42:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 23 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE20A DE20A-May06-23-40-23 2007-05-07 00:42:04.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 1 HINT Var-1 label=P It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:05.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 2 HINT Var-1 label=P Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II 18 DE20A DE20A-May06-23-40-23 2007-05-07 00:42:10.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DRAW-AXES 0) 3 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II 19 DE20A DE20A-May06-23-40-23 2007-05-07 00:42:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 HINT Var-1 label=P Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-POWER-VAR USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:20.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 HINT #.(wb-quant '(define-variable "A" |NIL| |area| |collector| |NIL| |NIL| NIL "") 'NIL) Right. What is the first principle application that you would like to work on? Hint: this principle application will usually be one that mentions the sought quantity explicitly. Therefore its equation may contain the sought quantity that the problem seeks. 2 DEFINE-POWER-VAR USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:27.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 3 HINT uniform-intensity-to-power Right indeed. A good step would be introducing a variable for the power supplied to the collector from the sunlight at T0. 3 DEFINE-POWER-VAR USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:28.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 4 HINT Define a variable for the power supplied to the collector from the sunlight at T0 by using the Add Variable command on the Variable menu and selecting power 4 4 DEFINE-POWER-VAR USNA SP212 General Physics II 14 DE20A DE20A-May06-23-40-23 2007-05-07 00:42:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 5 CORRECT Var-5 label="PC";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:46.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 HINT Why don't you continue with the solution by working on relating the intensity to power (uniform intensity). 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 HINT If the power going through the collector is constant, then the intensity is the power divided by the area of the collector. 2 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:47.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 3 HINT The power going through a surface is just the intensity times the area of the surface. 3 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:42:48.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 4 HINT Write the equation PC = A * I 4 4 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 9 DE20A DE20A-May06-23-40-23 2007-05-07 00:42:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 5 CORRECT 0 "PC=A*I" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 53 (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1)) DE20A DE20A-May06-23-40-23 2007-05-07 00:43:06.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 CORRECT 1 "P=0.28*PC" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE20A DE20A-May06-23-40-23 2007-05-07 00:43:10.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DE20A DE20A-May06-23-40-23 2007-05-07 00:43:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 84 DE20A DE20A-May06-23-43-30 2007-05-07 00:44:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 14 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE20A DE20A-May06-23-43-30 2007-05-07 00:44:24.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-2 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 1 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 2 HINT You should use the body tool to draw a body choosing the sail as the body. 2 2 DRAW-BODY USNA SP212 General Physics II 9 DE20A DE20A-May06-23-43-30 2007-05-07 00:45:10.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 3 INCORRECT Axes-3 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-BODY USNA SP212 General Physics II 7 DE20A DE20A-May06-23-43-30 2007-05-07 00:45:26.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (BODY SAIL TIME NIL) 4 CORRECT System-4 label="s";body=sail;time=NIL DRAW-BODY USNA SP212 General Physics II 19 DE20A DE20A-May06-23-43-30 2007-05-07 00:45:28.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 HINT Vector-5 label=F You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:29.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 HINT Vector-5 label=F Try introducing a variable for the magnitude of the pressure force on the sail at T0 due to the sunlight. 2 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:30.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 3 HINT Vector-5 label=F A force is exerted on the sail by the sunlight 3 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:31.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 4 HINT Vector-5 label=F When radiation is absorbed by (or is reflected off) a body, it exerts a pressure force on that body which is proportional to the intensity of the radiation. 4 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:32.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 5 HINT Vector-5 label=F Because the sunlight exerts a pressure against the sail, draw a pressure force on the sail due to the sunlight acting at an unknown angle. 5 5 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II 14 DE20A DE20A-May06-23-43-30 2007-05-07 00:45:47.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 6 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=94 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 HINT Why don't you continue working on entering the given value of the magnitude of the pressure force on the sail at T0 due to the sunlight. 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:50.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 2 HINT You can find the value of the magnitude of the pressure force on the sail at T0 due to the sunlight in the problem statement. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 3 HINT The value of the magnitude of the pressure force on the sail at T0 due to the sunlight is given as 20 mN. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:45:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 4 HINT Enter the equation F = 20 mN. 4 4 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 9 DE20A DE20A-May06-23-43-30 2007-05-07 00:45:58.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 5 CORRECT 0 "F=20 mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 17 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE20A DE20A-May06-23-43-30 2007-05-07 00:46:10.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What is one quantity that the problem is seeking? 1 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:15.0 US/Eastern HINT_REQUEST Choose-Sought HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 2 HINT #.(wb-quant '(define-variable "P" |NIL| |pressure| |sail| |T0| |NIL| NIL "") 'NIL) Very good. What is the first principle application that you would like to work on? Hint: usually this principle application will usually mention one of the sought quantities explicitly. That is, its equation may contain one of the sought quantities that the problem seeks. 2 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:35.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG Ask-Principle Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 3 HINT intensity-to-poynting-vector-magnitude No principle applications of the type that you selected appear in the solution. What is the first principle application that you wish to work on? You should look for a principle that contains the sought quantity itself. 3 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:36.0 US/Eastern HINT_REQUEST Choose-Principle HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 4 HINT intensity-to-decibels No principle applications of the type that you selected appear in the solution. Lets just assume that you will work on finding the radiation pressure on the sail due to the sunlight. 4 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:37.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 5 HINT the sunlight reflects off the sail. 5 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 6 HINT Light waves carry a small amount of momentum. When they reflect off a surface, they exert a force on that surface. 6 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:38.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 7 HINT Write the equation P = (2 * I) / c 7 7 WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 12 DE20A DE20A-May06-23-43-30 2007-05-07 00:46:49.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 8 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 32 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE20A DE20A-May06-23-43-30 2007-05-07 00:46:51.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:46:55.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Answer-1 "8.672666475151953e-6 Pa" DEFINE-AREA USNA SP212 General Physics II 49 DE20A DE20A-May06-23-43-30 2007-05-07 00:47:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 2 INCORRECT 3 "F = P/A" Undefined variable: A 1 DEFINE-AREA USNA SP212 General Physics II 48 DE20A DE20A-May06-23-43-30 2007-05-07 00:47:13.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 3 CORRECT Var-6 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:47:17.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 INCORRECT 4 "A" Unable to solve for A. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:47:27.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "P=F/A" PRESSURE-FORCE USNA SP212 General Physics II 68 (= Pr_SAIL (/ Fp_SAIL_SUNLIGHT_1 A_SAIL)) DE20A DE20A-May06-23-43-30 2007-05-07 00:47:30.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 CORRECT 4 "A" USNA SP212 General Physics II DE20A DE20A-May06-23-43-30 2007-05-07 00:47:35.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 " 2306.095830769231 m^2" USNA SP212 General Physics II 79 DE20A DE20A-May06-23-47-50 2007-05-07 00:48:07.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 1 INCORRECT System-1 label="e";body=earth;time=NIL DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:48:36.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 1 INCORRECT Var-2 label="s02";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="3.84e8 m" The value of s02 is not given in this problem. It should be marked unknown. 1 1 DEFINE-DISTANCE USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:48:42.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 3))) 2 CORRECT Var-2 label="s02";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T2;value="" DEFINE-DISTANCE USNA SP212 General Physics II 2 DE20A DE20A-May06-23-47-50 2007-05-07 00:48:50.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 2 HINT It is a good idea to begin any problem by enumerating the bodies at work within it. Doing so helps to frame later principle applications. Why don't you do so now. 1 DRAW-BODY USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:48:51.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 3 HINT You should use the body tool to draw a body choosing the pulse as the body. 2 2 DRAW-BODY USNA SP212 General Physics II -3 DE20A DE20A-May06-23-47-50 2007-05-07 00:48:59.0 US/Eastern ATTEMPT Body RESULT Electromagnetic Waves WAVE* WAVE19 (BODY PULSE TIME NIL) 4 CORRECT System-3 label="p";body=pulse;time=NIL DRAW-BODY USNA SP212 General Physics II -2 DE20A DE20A-May06-23-47-50 2007-05-07 00:49:03.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 1 HINT It is now a good idea for you to draw an axis. This will help to ground your work and be useful later on in the process. 1 DRAW-UNROTATED-AXES USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:04.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 2 HINT Why don't you draw a pair of standard axes setting the positive X axis at 0 degrees. 2 2 DRAW-UNROTATED-AXES USNA SP212 General Physics II -7 DE20A DE20A-May06-23-47-50 2007-05-07 00:49:08.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves WAVE* WAVE19 (DRAW-AXES 0) 3 CORRECT Axes-4 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II -6 DE20A DE20A-May06-23-47-50 2007-05-07 00:49:11.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 1 HINT At this point it would be a good idea to begin enumerating all of the useful given quantities in the problem 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 2 HINT why don't you start with entering the given value of the distance travelled by the pulse from T0 to T1. 2 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:12.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 3 HINT Try introducing a variable for the distance travelled by the pulse from T0 to T1. 3 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:13.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_12 (DNUM 3.84e+8 m))) 4 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T0 to T1. 4 4 DEFINE-DISTANCE USNA SP212 General Physics II -11 DE20A DE20A-May06-23-47-50 2007-05-07 00:49:26.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 1 INCORRECT Var-5 label="s01";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="" The value of s01 can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II -12 DE20A DE20A-May06-23-47-50 2007-05-07 00:49:43.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 2 INCORRECT Var-5 label="s01";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="1.92e8 m" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II (= dist_PULSE_12 (DNUM 1.92e+8 m)) DE20A DE20A-May06-23-47-50 2007-05-07 00:49:49.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 1 2))) 3 CORRECT Var-5 label="s01";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T0 to T1;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II -3 (= dist_PULSE_12 (DNUM 3.84e+8 m)) DE20A DE20A-May06-23-47-50 2007-05-07 00:49:54.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 1 HINT You should finish entering all of the useful given quantities in the problem. Why don't you work on entering the given value of the distance travelled by the pulse from T1 to T2. 1 DEFINE-DISTANCE USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 2 HINT A good step would be introducing a variable for the distance travelled by the pulse from T1 to T2. 2 DEFINE-DISTANCE USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:49:56.0 US/Eastern HINT_REQUEST Explain-Further HINT_MSG NextStepHelp Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 3 HINT Use the distance menu item under the Variables menu to define a variable for the distance travelled by the pulse from T1 to T2. 3 3 DEFINE-DISTANCE USNA SP212 General Physics II -8 DE20A DE20A-May06-23-47-50 2007-05-07 00:50:11.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DISTANCE PULSE TIME (DURING 2 3))) 4 CORRECT Var-6 label="s12";quant=distance;subtype=NIL;body=pulse;agent=NIL;time=T1 to T2;value="3.84e8 m" DEFINE-DISTANCE USNA SP212 General Physics II 2 (= dist_PULSE_23 (DNUM 3.84e+8 m)) DE20A DE20A-May06-23-47-50 2007-05-07 00:50:13.0 US/Eastern HINT_REQUEST NextStepHelp HINT_MSG Ask-Sought Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 1 HINT Now that you have stated all of the given information, you should start on the major principles. What quantity is the problem seeking? 1 DEFINE-DURATION USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:50:36.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves WAVE* WAVE19 (DEFINE-VAR (DURATION (DURING 1 3))) 2 CORRECT Var-7 label="t";quant=duration;subtype=NIL;body=NIL;agent=NIL;time=T0 to T2;value="" DEFINE-DURATION USNA SP212 General Physics II 3 DE20A DE20A-May06-23-47-50 2007-05-07 00:50:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 c)) 1 CORRECT 0 "s02=c*t" WRITE-WAVE-SPEED-LIGHT USNA SP212 General Physics II 46 (= dist_PULSE_13 (* c t_13)) DE20A DE20A-May06-23-47-50 2007-05-07 00:50:54.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= sp_PULSE_13 (/ dist_PULSE_13 t_13))) 1 CORRECT 0 "s02=c*t" WRITE-SDD USNA SP212 General Physics II 46 (= dist_PULSE_13 (* c t_13)) DE20A DE20A-May06-23-47-50 2007-05-07 00:51:04.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves WAVE* WAVE19 (EQN (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23))) 1 CORRECT 1 "s02=s01+s12" WRITE-SUM-DISTANCES USNA SP212 General Physics II 47 (= dist_PULSE_13 (+ dist_PULSE_12 dist_PULSE_23)) DE20A DE20A-May06-23-47-50 2007-05-07 00:51:09.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves WAVE* WAVE19 CALC_REQUEST 1 CORRECT 2 "t" USNA SP212 General Physics II DE20A DE20A-May06-23-47-50 2007-05-07 00:51:14.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves WAVE* WAVE19 Answer-1 1 CORRECT Answer-1 "2.5617722511218077 s" USNA SP212 General Physics II 78 DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:01.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/," Syntax error in E=120 V/ 1 DEFINE-AMPLITUDE USNA SP212 General Physics II ? DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:08.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE ELECTRIC)) 2 CORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" DEFINE-AMPLITUDE USNA SP212 General Physics II 22 (= ampE_WAVE (DNUM 120 V/m)) DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:16.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 CORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" DEFINE-AMPLITUDE USNA SP212 General Physics II 23 DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:21.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (* c ampM_WAVE))) 1 CORRECT 0 "E=c*B" WRITE-ELECTROMAGNETIC-WAVE-FIELD-AMPLITUDE USNA SP212 General Physics II 67 (= ampE_WAVE (* c ampM_WAVE)) DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:25.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE1 CALC_REQUEST 1 CORRECT 1 "B" USNA SP212 General Physics II DE22B DE22B-Apr08-22-45-48 2007-04-08 23:46:30.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE1 Answer-1 1 CORRECT Answer-1 "4.0027691423778244e-7 T" USNA SP212 General Physics II 98 DE22B DE22B-Apr08-22-48-02 2007-04-08 23:50:06.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (NET-POWER-OUT TRANSMITTER TIME 1)) 1 CORRECT Var-1 label="P";quant=net-power-out;subtype=NIL;body=transmitter;agent=NIL;time=T0;value="280 kW" DEFINE-NET-POWER-OUT USNA SP212 General Physics II 16 (= power_TRANSMITTER_1 (DNUM 280 kW)) DE22B DE22B-Apr08-22-48-02 2007-04-08 23:51:30.0 US/Eastern ATTEMPT Axes RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DRAW-AXES 0) 1 CORRECT Axes-2 body=NIL;dir=0;x_label="x";y_label="y";z_label="z" DRAW-UNROTATED-AXES USNA SP212 General Physics II DE22B DE22B-Apr08-22-48-02 2007-04-08 23:51:55.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (VECTOR (RELATIVE-POSITION P TRANSMITTER TIME 1) (DNUM 0 deg)) 1 CORRECT Vector-3 label="r";type=Position;body=P;agent=transmitter;time=T0;dir=0;mag=198 DRAW-RELATIVE-POSITION USNA SP212 General Physics II DE22B DE22B-Apr08-22-48-02 2007-04-08 23:54:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 1 INCORRECT 0 "r= 9 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 14 (= r_P_TRANSMITTER_1 (DNUM 9 km)) DE22B DE22B-Apr08-22-48-02 2007-04-08 23:54:19.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= r_P_TRANSMITTER_1 (DNUM 8.0 km))) 2 CORRECT 0 "r= 8 km" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 24 (= r_P_TRANSMITTER_1 (DNUM 8 km)) DE22B DE22B-Apr08-22-48-02 2007-04-08 23:54:41.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 1 INCORRECT 1 "P=4*$p*(r^2)*l" Undefined variable: l 1 DEFINE-INTENSITY USNA SP212 General Physics II 23 DE22B DE22B-Apr08-22-48-02 2007-04-08 23:56:18.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (DEFINE-VAR (INTENSITY P TRANSMITTER TIME 1)) 2 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=P;agent=transmitter;time=T0;value="" DEFINE-INTENSITY USNA SP212 General Physics II DE22B DE22B-Apr08-22-48-02 2007-04-08 23:56:20.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE3A (EQN (= power_TRANSMITTER_1 (* 4 $P (^ r_P_TRANSMITTER_1 2) int_P_TRANSMITTER_1))) 1 CORRECT 1 "P=4*$p*(r^2)*I" WRITE-SPHERICAL-INTENSITY-TO-POWER USNA SP212 General Physics II 67 (= power_TRANSMITTER_1 (* (* (* 4 $P) (^ r_P_TRANSMITTER_1 2)) int_P_TRANSMITTER_1)) DE22B DE22B-Apr08-22-48-02 2007-04-08 23:56:24.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE3A CALC_REQUEST 1 CORRECT 2 "I" USNA SP212 General Physics II DE22B DE22B-Apr08-22-48-02 2007-04-08 23:56:29.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE3A Answer-1 1 CORRECT Answer-1 " 3.4815143801352105e-4 W/m^2" USNA SP212 General Physics II 98 DE22B DE22B-Apr08-22-57-22 2007-04-08 23:58:26.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (INTENSITY COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-1 label="I";quant=intensity;subtype=NIL;body=collector;agent=sunlight;time=T0;value="960 W/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 16 (= int_COLLECTOR_SUNLIGHT_1 (DNUM 960 W/m^2)) DE22B DE22B-Apr08-22-57-22 2007-04-08 23:58:57.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (AREA COLLECTOR)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=collector;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE22B DE22B-Apr08-22-57-22 2007-04-08 23:59:58.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 1 CORRECT Var-3 label="P";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE22B DE22B-Apr08-22-57-22 2007-04-09 00:00:01.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER COLLECTOR SUNLIGHT TIME 1)) 2 CORRECT Var-3 label="Ps";quant=power;subtype=NIL;body=collector;agent=sunlight;time=T0;value="" DEFINE-POWER-VAR USNA SP212 General Physics II DE22B DE22B-Apr08-22-57-22 2007-04-09 00:01:37.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (DEFINE-VAR (POWER ELECTRIC_OUTPUT COLLECTOR TIME 1)) 1 CORRECT Var-4 label="P";quant=power;subtype=NIL;body=electric_output;agent=collector;time=T0;value="2 MW" DEFINE-POWER-VAR USNA SP212 General Physics II 25 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 2 MW)) DE22B DE22B-Apr08-22-57-22 2007-04-09 00:01:44.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 0 "PA-I A" Syntax error in PA-I A 1 WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 24 ? DE22B DE22B-Apr08-22-57-22 2007-04-09 00:02:22.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_COLLECTOR_SUNLIGHT_1 (* A_COLLECTOR int_COLLECTOR_SUNLIGHT_1))) 2 CORRECT 0 "Ps=I*A" WRITE-UNIFORM-INTENSITY-TO-POWER USNA SP212 General Physics II 68 (= power_COLLECTOR_SUNLIGHT_1 (* int_COLLECTOR_SUNLIGHT_1 A_COLLECTOR)) DE22B DE22B-Apr08-22-57-22 2007-04-09 00:03:03.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 1 INCORRECT 1 "P=.28s" Units are inconsistent. 1 1 GIVEN-FRACTION USNA SP212 General Physics II 67 (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (DNUM 0.28 s)) DE22B DE22B-Apr08-22-57-22 2007-04-09 00:03:06.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 2 INCORRECT 1 "P=.28sdf" Syntax error in P=.28sdf 1 GIVEN-FRACTION USNA SP212 General Physics II ? DE22B DE22B-Apr08-22-57-22 2007-04-09 00:03:15.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE4 (EQN (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1))) 3 CORRECT 1 "P=.28*Ps" GIVEN-FRACTION USNA SP212 General Physics II (= power_ELECTRIC_OUTPUT_COLLECTOR_1 (* 0.28 power_COLLECTOR_SUNLIGHT_1)) DE22B DE22B-Apr08-22-57-22 2007-04-09 00:03:53.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE4 CALC_REQUEST 1 CORRECT 2 "A" USNA SP212 General Physics II DE22B DE22B-Apr08-22-57-22 2007-04-09 00:04:00.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE4 Answer-1 1 CORRECT Answer-1 "7440.476190476189 m^2" USNA SP212 General Physics II 98 DE22B DE22B-Apr08-23-04-33 2007-04-09 00:05:00.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (PRESSURE SAIL TIME 1)) 1 CORRECT Var-1 label="P";quant=pressure;subtype=NIL;body=sail;agent=NIL;time=T0;value="" DEFINE-PRESSURE USNA SP212 General Physics II 6 DE22B DE22B-Apr08-23-04-33 2007-04-09 00:05:19.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (AREA SAIL)) 1 CORRECT Var-2 label="A";quant=area;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-AREA USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:05:28.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 1 INCORRECT Var-3 label="g";quant=gravitational-acceleration;subtype=NIL;body=sail;agent=NIL;time=NIL;value="" DEFINE-INTENSITY USNA SP212 General Physics II 4 DE22B DE22B-Apr08-23-04-33 2007-04-09 00:05:50.0 US/Eastern ATTEMPT Variable RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (DEFINE-VAR (INTENSITY SAIL SUNLIGHT TIME 1)) 2 CORRECT Var-4 label="I";quant=intensity;subtype=NIL;body=sail;agent=sunlight;time=T0;value="1.3 kW/m^2" DEFINE-INTENSITY USNA SP212 General Physics II 12 (= int_SAIL_SUNLIGHT_1 (DNUM 1.3 kW/m^2)) DE22B DE22B-Apr08-23-04-33 2007-04-09 00:05:56.0 US/Eastern ATTEMPT Equation RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 1 INCORRECT 0 "F=20mN" Undefined variable: F 1 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:15.0 US/Eastern ATTEMPT Vector RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (VECTOR (FORCE SAIL SUNLIGHT PRESSURE TIME 1) UNKNOWN) 2 CORRECT Vector-5 label="F";type=Force;body=sail;agent=sunlight;forcetype=Pressure;time=T0;dir=NIL;mag=125 DRAW-PRESSURE-UNKNOWN USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:31.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN))) 1 CORRECT 0 "F=20mN" WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II 21 (= Fp_SAIL_SUNLIGHT_1 (DNUM 20 mN)) DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:42.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c))) 1 CORRECT 1 "P=(2*I)/c" WRITE-RADIATION-PRESSURE USNA SP212 General Physics II 40 (= Pr_SAIL (/ (* 2 int_SAIL_SUNLIGHT_1) c)) DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:45.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 1 CORRECT 2 "P" USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:50.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 2 CORRECT Answer-1 " 8.672666475151953e-6 Pa" USNA SP212 General Physics II 57 DE22B DE22B-Apr08-23-04-33 2007-04-09 00:06:55.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 3 INCORRECT 3 "A" Unable to solve for A. Try the light-bulb if you need a hint about a step that still needs to be done. 1 1 USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:07:00.0 US/Eastern ATTEMPT Equation RESULT Electromagnetic Waves EMWAVE* EMWAVE5 (EQN (= Fp_SAIL_SUNLIGHT_1 (* Pr_SAIL A_SAIL))) 1 CORRECT 3 "F=A*P" PRESSURE-FORCE USNA SP212 General Physics II 77 (= Fp_SAIL_SUNLIGHT_1 (* A_SAIL Pr_SAIL)) DE22B DE22B-Apr08-23-04-33 2007-04-09 00:07:03.0 US/Eastern CALC_REQUEST Solve CALC_RESULT Electromagnetic Waves EMWAVE* EMWAVE5 CALC_REQUEST 4 CORRECT 4 "A" USNA SP212 General Physics II DE22B DE22B-Apr08-23-04-33 2007-04-09 00:07:09.0 US/Eastern ATTEMPT Answer RESULT Electromagnetic Waves EMWAVE* EMWAVE5 Answer-2 1 CORRECT Answer-2 "2306.095830769231 m^2" USNA SP212 General Physics II 88 DE24F DE24F-May07-10-16-37 2007-05-07 11:17:04.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (EQN (= ampE_WAVE (DNUM 120 V/m))) 1 INCORRECT Var-1 label="E";quant=amplitude-electric;subtype=NIL;body=wave;agent=NIL;time=NIL;value="" The value of E can be determined from the problem statement. It should be entered in the dialog box when defining the relevant variable. 1 1 WRITE-KNOWN-VALUE-EQN USNA SP212 General Physics II DE24F DE24F-May07-10-16-37 2007-05-07 11:17:20.0 US/Eastern ATTEMPT Variable RESULT Unsolicited Electromagnetic Waves EMWAVE* EMWAVE1 (DEFINE-VAR (AMPLITUDE WAVE TYPE MAGNETIC)) 1 INCORRECT Var-2 label="B";quant=amplitude-magnetic;subtype=NIL;body=wave;agent=NIL;time=NIL;value="120 V/m" The value of B is not given in this problem. It should be marked unknown. 1 1 DEFINE-AMPLITUDE USNA SP212 General Physics II