// Numbas version: finer_feedback_settings {"name": "USSKL6-30-1 Scientific Basis of Engineering Combined Written Assessment", "metadata": {"description": "

Simple Veriosn of Exam with randomised values

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Question Covering AC power and frquency response

", "licence": "All rights reserved"}, "statement": "

Power & Frequency Response

", "advice": "

see spread sheet

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"Q3ai_f_S": {"name": "Q3ai_f_S", "group": "Q3a", "definition": "random(100 .. 150#10)", "description": "

Frequency (fs)

", "templateType": "randrange", "can_override": false}, "Q3ai_V_PP": {"name": "Q3ai_V_PP", "group": "Q3a", "definition": "random(5 .. 9#1)", "description": "

VP-P

", "templateType": "randrange", "can_override": false}, "Q3ai_V_DC": {"name": "Q3ai_V_DC", "group": "Q3a", "definition": "random(-0.5 .. 0.5#0.2)", "description": "

DC Offset

", "templateType": "randrange", "can_override": false}, "Q3ai_R_L": {"name": "Q3ai_R_L", "group": "Q3a", "definition": "random(50 .. 150#10)", "description": "

Load Resistor RL

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Frequency (fs)

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VP-P

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RL

", "templateType": "randrange", "can_override": false}, "Q3aii_t_rise": {"name": "Q3aii_t_rise", "group": "Q3a", "definition": "siground(dec(1/(Q3aii_t_rise_modifier*q3aii_f_s)),4)", "description": "", "templateType": "anything", "can_override": false}, "Q3aii_t_rise_modifier": {"name": "Q3aii_t_rise_modifier", "group": "Q3a", "definition": "random(3 .. 4#1)", "description": "

Modifier of t_rise

", "templateType": "randrange", "can_override": false}, "Q3aii_V_DC": {"name": "Q3aii_V_DC", "group": "Q3a", "definition": "random(1 .. 1#1)", "description": "

DC Offset

", "templateType": "randrange", "can_override": false}, "Q3b_R1": {"name": "Q3b_R1", "group": "Q3b", "definition": "random(3000 .. 3600#100)", "description": "", "templateType": "randrange", "can_override": false}, "Q3b_R2": {"name": "Q3b_R2", "group": "Q3b", "definition": "random(2000 .. 2000#1000)", "description": "", "templateType": "randrange", "can_override": false}, "Q3b_R3": {"name": "Q3b_R3", "group": "Q3b", "definition": "random(1800 .. 2000#500)", "description": "", "templateType": "randrange", "can_override": false}, "Q3b_R4": {"name": "Q3b_R4", "group": "Q3b", "definition": "random(10000 .. 20000#2000)", "description": "", "templateType": "randrange", "can_override": false}, "Q3b_VS": {"name": "Q3b_VS", "group": "Q3b", "definition": "random(12 .. 12#1)", "description": "", "templateType": "randrange", "can_override": false}, "Q3c_R_L": {"name": "Q3c_R_L", "group": "Q3d", "definition": "random(1 .. 3#1)", "description": "

Load Resistance (kΩ)

", "templateType": "randrange", "can_override": false}, "Q3c_C1": {"name": "Q3c_C1", "group": "Q3d", "definition": "random(1 .. 3#1)", "description": "

Smoothing Capacitor (uF)

", "templateType": "randrange", "can_override": false}, "Q3c_V_S": {"name": "Q3c_V_S", "group": "Q3d", "definition": "random(20 .. 23#1)", "description": "

Supply Voltage (VS)

", "templateType": "randrange", "can_override": true}, "Q3c_Z_BDV": {"name": "Q3c_Z_BDV", "group": "Q3d", "definition": "siground(dec(q3c_v_s*(3/20)),2)", "description": "

Zener Diode Reverse Breakdown Voltage (V)

", "templateType": "anything", "can_override": false}, "Q3d_C1": {"name": "Q3d_C1", "group": "Q4d", "definition": "random(10 .. 12#0.1)", "description": "

Capacitance C1

", "templateType": "randrange", "can_override": false}, "Q3d_L1": {"name": "Q3d_L1", "group": "Q4d", "definition": "random(170 .. 190#10)", "description": "

Inductance

", "templateType": "randrange", "can_override": false}, "Q3d_R_L": {"name": "Q3d_R_L", "group": "Q4d", "definition": "random(1 .. 5#4)", "description": "", "templateType": "randrange", "can_override": false}, "Q3d_V_S": {"name": "Q3d_V_S", "group": "Q4d", "definition": "random(1 .. 10#9)", "description": "", "templateType": "randrange", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": [], "variable_groups": [{"name": "Unnamed group", "variables": []}, {"name": "Q3b", "variables": ["Q3b_R1", "Q3b_R2", "Q3b_R3", "Q3b_R4", "Q3b_VS"]}, {"name": "Q3a", "variables": ["Q3ai_f_S", "Q3ai_R_L", "Q3ai_V_DC", "Q3ai_V_PP", "q3aii_f_s", "Q3aii_R_L", "Q3aii_t_rise", "Q3aii_t_rise_modifier", "Q3aii_V_DC", "q3aii_v_pp"]}, {"name": "Q3d", "variables": ["Q3c_R_L", "Q3c_C1", "Q3c_V_S", "Q3c_Z_BDV"]}, {"name": "Q4d", "variables": ["Q3d_C1", "Q3d_V_S", "Q3d_L1", "Q3d_R_L"]}], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) Signal Waveforms

\n

Draw or derive the voltage and current wave forms for the following:

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Waveform\n

Varibles

\n
\n

Circuit

\n
i. Sinusoidal \n

RL: {Q3ai_R_L} Ω

\n

Frequency (fs): {Q3ai_F_S} Hz

\n

VP-P: {Q3ai_V_PP} V

\n

DC Offset (VDC): {Q3ai_V_DC} V

\n
\n

\n

\"Simple

\n
ii. Triangular\n

RL: {Q3aii_R_L/1000} kΩ

\n

Frequency (fs): {Q3aii_F_S} Hz

\n

VP-P: {Q3aii_V_PP} V

\n

DC Offset (VDC): {Q3aii_V_DC} V

\n

tRise: {Q3aii_t_rise*1000} ms

\n
\n

\"Simple

\n
\n

\n

SPICE Circuit suitable for analysis: SbE CC1 Q3a (multisim.com)

\n

\n

[4Marks]

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Part b) Power Calculation

\n

The figure shows a resistor network connected to a Triangular Waveform source and the equations that can be used to convert between Star and Delta impedance configurations:

\n

\"Resistor

\n

Circuit Varibles: VS(peak) = {Q3b_VS}V, f = {100}Hz trise = {2}ms Hz, R1= {siground(dec(Q3b_R1/1000),2)}kΩ, R2= {siground(dec(Q3b_R2/1000),2)}kΩ, R3= {siground(dec(Q3b_R3/1000),2)}kΩ, R4= {siground(dec(Q3b_R4/1000),2)}kΩ

\n

For the values given, calculate or determine the RMS power dissipated in the whole circuit and resistor R­1

\n

SPICE Circuit Suitable for Analysis: *SbE CC1 Q3b (multisim.com)

\n

[6Marks]

\n

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Part c) Power Supply

\n

The figure shows a circuit designed for Voltage Reduction, Rectification and Regulation of an AC power source. 

\n

\n

Circuit Variables: VS = {Q3c_V_S}VRMS; C1 = {Q3c_C1}mF; R1={1}Ω; RL = {Q3c_R_L}kΩ; T1: Turns on Primary Winding,  NP = 20 and Secondary NS = 9;  Diodes D1 & D2, Forward Bias Voltage = 860mV; Diode Z1, Reverse Breakdown Voltage = {Q3c_Z_BDV}V.  

\n

For the component values given, explain how the circuit operates.  Ensure that you:

\n\n

SPICE Circuit Suitable for Analysis: SbE CC1 EL Q3c (multisim.com)

\n

[8 Marks]

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Part d) Frequency Response

\n

The circuit shown has a capacitor and inductor in parallel which has been designed to be in resonance at a known frequency.  The signal is measured across the load (RL).

\n

\n

\n

Circuit Varibles: VS = {Q3d_V_S}V(RMS) , RL = {Q3d_R_L} kΩ C1 = {Q3d_C1}μF L1 = {Q3d_L1} mH

\n

Using calculation or simulation, evaluate the performance of the circuit in a frequency range from 1Hz to 10kHz.  Ensure that you:

\n\n

SPICE Circuit Suitable for Analysis: *SbE CC1 Q3d (multisim.com)

\n

\n

[12 Marks]

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Question covering DC and Step response circuits

", "licence": "All rights reserved"}, "statement": "

Steady State & Step Response

", "advice": "

See Spread Sheet

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true, "j": false}, "constants": [], "variables": {"Q2b_R3": {"name": "Q2b_R3", "group": "Ungrouped variables", "definition": "q2b_rs1", "description": "

M

\n

", "templateType": "anything", "can_override": false}, "Q2b_Resistivity": {"name": "Q2b_Resistivity", "group": "Ungrouped variables", "definition": "random(640 .. 640#10)", "description": "

Resistivity of Silicon (Ωm)

", "templateType": "randrange", "can_override": false}, "Q2b_VS": {"name": "Q2b_VS", "group": "Ungrouped variables", "definition": "random(9 .. 12#1)", "description": "

Supply Voltage V

", "templateType": "randrange", "can_override": false}, "Q2b_R1": {"name": "Q2b_R1", "group": "Ungrouped variables", "definition": "random(4000000 .. 7000000#1000000)", "description": "

Resistance of R1 in MΩ

", "templateType": "randrange", "can_override": false}, "Q2b_R2": {"name": "Q2b_R2", "group": "Ungrouped variables", "definition": "Q2b_R1", "description": "", "templateType": "anything", "can_override": false}, "Q2b_A1": {"name": "Q2b_A1", "group": "Ungrouped variables", "definition": "random(1 .. 2#1)", "description": "

Cross Sectional Area mm2

", "templateType": "randrange", "can_override": false}, "Q2b_l1": {"name": "Q2b_l1", "group": "Ungrouped variables", "definition": "random(10 .. 10#1)", "description": "

length pf gauge mm

", "templateType": "randrange", "can_override": false}, "Q2b_Volume_of_Sample": {"name": "Q2b_Volume_of_Sample", "group": "Ungrouped variables", "definition": "dec(q2b_a1/1000000)*dec(Q2b_l1/1000)\n", "description": "", "templateType": "anything", "can_override": false}, "Q2b_l2": {"name": "Q2b_l2", "group": "Ungrouped variables", "definition": "random(10.1 .. 10.2#0.1)", "description": "

Length of sample after load is applied (mm)

", "templateType": "randrange", "can_override": false}, "Q2b_A2": {"name": "Q2b_A2", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Volume_of_Sample/(Q2b_l2/1000))*1000000),4)\n", "description": "

Cross Sectional Area of Guage when load is applied mm2

", "templateType": "anything", "can_override": false}, "Q2b_RS1": {"name": "Q2b_RS1", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Resistivity*(Q2b_l1/1000))/(Q2b_a1/1000000)),4)\n", "description": "", "templateType": "anything", "can_override": false}, "Q2b_RS2": {"name": "Q2b_RS2", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Resistivity*(Q2b_l2/1000))/(Q2b_a2/1000000)),4)", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Q2b_Resistivity", "Q2b_VS", "Q2b_R1", "Q2b_R2", "Q2b_R3", "Q2b_A1", "Q2b_l1", "Q2b_Volume_of_Sample", "Q2b_l2", "Q2b_A2", "Q2b_RS1", "Q2b_RS2"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a. Circuit Symbols

\n

For each of the symbols shown in the table, state the name and function of the device: 

\n

\"Circuit

\n

[4 Marks]

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Part b. Wheatstone Bridge Calculation

\n

A Wheatstone Bridge is used to measure the change of resistance before & while a load is applied to a gauge block made of silicon material with resistivity ρ = {Q2b_Resistivity}Ωm.

\n

\"Wheatstone

\n

Circuit Varibles:  VS = {Q2b_VS} V, R1 = {siground({Q2b_R1}/1000000,2)} MΩ,  R2 = {siground({Q2b_R2}/1000000,2)} MΩ, R3 = {siground({Q2b_R3}/1000000,2)} MΩ

\n

\n

The dimensions of the gauge before the load is applied are: Cross Sectional Area, A1  = {Q2b_A1} mm2, length, l1 = {Q2b_l1} mm.   

\n

The dimensions of the gauge when the load is applied are: Cross Sectional Area, A2 = {Q2b_A2} mm2, length, l2 = {Q2b_l2} mm.   

\n\n

SPICE circuit suitable for analysis:  SbE CC1 Q1b (multisim.com)

\n

[6 Marks]

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Part c. Step Response

\n

The circuit shows a Resistor and Capacitor Network as well as the charge/discharge plots of the Capacitor when the switch is closed and opened.

\n

\n

Circuit Varibles: VS = {5} V, VB = {2.5} V tON ={50} ms, tOFF ={200} ms C1 ={10} μF , R1 = {10} kΩ, R2 = {2} kΩ

\n

 

\n

Explain what is happening in the circuit.  What is the relationship between the voltage across and current through the Capacitor.

\n

SPICE circuit suitable for analysis: SbE CC1 Q2c (multisim.com)

\n

[8 Marks]

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Part d. Circuit Analysis

\n

The circuit shown is for a simple ‘No Volt Release’ circuit configuration which is used as a safety feature on electrical equipment:

\n

\"No

\n

Analyse the operation of this circuit for the intended purpose. Ensure that you:

\n\n

SPICE circuit suitable for analysis: EveryCircuit - No Volt Release

\n

[12 Marks]

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Part b. Wheatstone Bridge Calculation

\n

A Wheatstone Bridge is used to measure the change of resistance before & while a load is applied to a gauge block made of silicon material with resistivity ρ = {Q2b_Resistivity}Ωm.

\n

\"Wheatstone

\n

Circuit Varibles:  VS = {Q2b_VS} V, R1 = {siground({Q2b_R1}/1000000,2)} MΩ,  R2 = {siground({Q2b_R2}/1000000,2)} MΩ, R3 = {siground({Q2b_R3}/1000000,2)} MΩ

\n

\n

The dimensions of the gauge before the load is applied are: Cross Sectional Area, A1  = {Q2b_A1} mm2, length, l1 = {Q2b_l1} mm.   

\n

The dimensions of the gauge when the load is applied are: Cross Sectional Area, A2 = {Q2b_A2} mm2, length, l2 = {Q2b_l2} mm.   

\n\n

SPICE circuit suitable for analysis:  SbE CC1 Q1b (multisim.com)

\n

[6 Marks]

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Question covering Solenoids, Motors and Semiconductors

", "licence": "All rights reserved"}, "statement": "

Electromechanical  Application & Control

", "advice": "

See Spreadsheet

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"Q4b_L1": {"name": "Q4b_L1", "group": "EL Q4b", "definition": "random(0.05 .. 0.05#1)", "description": "

Solenoid Inductace (L1)

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Solenoid Resistance (Ω)

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The length (l ) of the solenoid in mm

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the gap (g) between the solenoid and the armature in mm 

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Force (F) generated by the solenoid in N

", "templateType": "randrange", "can_override": false}, "Q4c_Duty_cycle": {"name": "Q4c_Duty_cycle", "group": "EL Q4c", "definition": "random(25 .. 60#5)", "description": "

PWM Duty Cycle

", "templateType": "randrange", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": [], "variable_groups": [{"name": "EL Q4a", "variables": []}, {"name": "EL Q4b", "variables": ["Q4b_L1", "Q4b_R1", "Q4b_Solenoid_length", "Q4b_Armature_Gap", "Q4b_F_gen"]}, {"name": "EL Q4c", "variables": ["Q4c_Duty_cycle"]}, {"name": "EL Q4d", "variables": []}], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) Semiconductor Circuit Symbols

\n

For each of the symbols shown in the table, state the name of the device and the function:

\n

\"Semiconductor

\n

\n

[4 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part b) Solenoid Calculation

\n

The figure shows a solenoid electromagnet circuit compromising the inductance of the coil and the series resistance.  It is being energised by a battery.  The switch has been closed for {100*Q4b_L1*Q4b_R1}s. 

\n

\"Solenoid

\n

The measured Inductance (L) of the solenoid is {siground(dec(Q4b_L1*1000),4)}mH and the Resistance is {Q4b_R1}Ω.  The length (l ) of the solenoid is {Q4b_Solenoid_length}mm and the gap (g) between the solenoid and the armature is {Q4b_Armature_Gap}mm. 

\n\n

[6Marks]

\n

SPICE circuit suitable for analysis:  SbE CC1 EL Q4b (multisim.com)

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part c) DC Motor Driver

\n

The figure shows a circuit used to drive a Permanent Magnet DC Motor.   

\n

\"DC

\n

Circuit Variables:

\n

VCC=12V; VPWM=5V, 1kz, {25}% Duty Cycle; R1 = 1kΩ;   Motor Armature Resistance RA = 1kΩ; Motor Inductance LA = 100μH;  Diode Reverse Breakdown Voltage = 1kV. 

\n

 

\n

Explain the operation of the circuit.  Ensure that you: 

\n\n

 

\n

SPICE circuit suitable for analysis:  SbE CC1 EL Q4c - Multisim Live

\n

 

\n

[8 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part d) Servo Vs Stepper Motor

\n

Simplified models of Servo Motor Control and a Stepper Motor Control are shown in shown in the figures below: 

\n

\"Stepper

\n

One of these technologies provides precision position control and the other provides precision motion control.  Compare the two technologies highlighting the advantages and disadvantages of each and for each suggest a suitable medical application that they would be best suited for. 

\n

Ensure that you give a brief description of how each motor control type functions. 

\n

[12 Marks]

"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question"}]}, {"name": "Me - Standard", "pickingStrategy": "all-ordered", "pickQuestions": 1, "questionNames": [""], "variable_overrides": [[]], "questions": [{"name": "MeQ7 - Friction & Centripetal Motion - Randomised Variables only", "extensions": [], "custom_part_types": [], "resources": [["question-resources/ME_Q7.png", "/srv/numbas/media/question-resources/ME_Q7.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}], "tags": [], "metadata": {"description": "

Friction & Centripital Motion

", "licence": "All rights reserved"}, "statement": "

Friction & Centripetal Motion

\n

An ambulance is making a turn along a road with a camber (θ = {MeQ7_Camber_theta}°) having a radius of curvature, r= {MeQ7_turn_radius}m. The mass of the ambulance is {MeQ7_Ambulance_Mass}kg.  The coefficient of static friction between the tyres and the road (μ) is {MeQ7_CoFriction}. The angle that the ambulance subtends while making the turn (β) is {MeQ7_Turn_Beta}°.

\n

\"Ambulance

\n

The ambulance is at the maximum safe speed so no slipping occurs.  

\n

\n

", "advice": "

see spreadsheet

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"MeQ7_Camber_theta": {"name": "MeQ7_Camber_theta", "group": "Ungrouped variables", "definition": "random(4 .. 7#1)", "description": "

Road camber (θ)

", "templateType": "randrange", "can_override": false}, "MeQ7_turn_radius": {"name": "MeQ7_turn_radius", "group": "Ungrouped variables", "definition": "random(90 .. 120#10)", "description": "

radius of curvature, r, (m)

", "templateType": "randrange", "can_override": false}, "MeQ7_Ambulance_Mass": {"name": "MeQ7_Ambulance_Mass", "group": "Ungrouped variables", "definition": "random(1000 .. 1200#30)", "description": "

The mass of the ambulance (kg)

", "templateType": "randrange", "can_override": false}, "MeQ7_CoFriction": {"name": "MeQ7_CoFriction", "group": "Ungrouped variables", "definition": "random(0.1 .. 0.3#0.1)", "description": "

The coefficient of static friction between the tyres and the road.

", "templateType": "randrange", "can_override": false}, "MeQ7_Turn_Beta": {"name": "MeQ7_Turn_Beta", "group": "Ungrouped variables", "definition": "random(45 .. 60#5)", "description": "

The angle that the ambulance subtends while making the turn

", "templateType": "randrange", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["MeQ7_Camber_theta", "MeQ7_turn_radius", "MeQ7_Ambulance_Mass", "MeQ7_CoFriction", "MeQ7_Turn_Beta"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) Use the vertical components of the forces acting on the ambulance to calculate the total normal reaction force (NC)

\n

[3marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part b) Resolve the horizontal forces acting on the Ambulance and write an expression that makes the normal reaction force the subject of the equation (i.e NC = ….).

\n

[3marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part c) Calculate the maximum safe speed in km/h so no slipping occurs?

\n

[3marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part d) How long does it take to complete the turn?

\n

[3marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part e) What kinetic energy will the ambulance have at the end of the turn?

\n

[3marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Ensure you include a free body diagram in your workings.

\n

[5 Marks]

"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question"}]}, {"name": "Me - Random", "pickingStrategy": "all-ordered", "pickQuestions": 1, "questionNames": ["", "", "", ""], "variable_overrides": [[], [], [], []], "questions": [{"name": "MeQ2 - Friction on an Incline Plane - Randomised Variables Only", "extensions": [], "custom_part_types": [], "resources": [["question-resources/UWESbeMeCC1_-_Q2_Friction_on_a_Slope.jpg", "/srv/numbas/media/question-resources/UWESbeMeCC1_-_Q2_Friction_on_a_Slope.jpg"], ["question-resources/UWESbeMeCC1_-_Q2_Crate_A_FBD.png", "/srv/numbas/media/question-resources/UWESbeMeCC1_-_Q2_Crate_A_FBD.png"], ["question-resources/UWESbeMeCC1_-_Q2_Crate_A_B_FBD.png", "/srv/numbas/media/question-resources/UWESbeMeCC1_-_Q2_Crate_A_B_FBD.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}], "tags": [], "metadata": {"description": "

2 bodies on an incline plane

", "licence": "All rights reserved"}, "statement": "

Friction on an Incline Plane

\n

Two blocks,  A & B,  rest on a slope at an angle of incline θ. 

\n

\"2

\n

The mass and coefficents of friction between the crates and the plane are:

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
mass (kg)Coefficient of Friction (μ)
Crate A{mass_crate_A}{co_eff_A}
Crate B{mass_crate_B}{co_eff_B}
", "advice": "

Worked answers to follow exam

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"Acc_Grav": {"name": "Acc_Grav", "group": "Ungrouped variables", "definition": "9.81", "description": "

Gravitational Constant

", "templateType": "number", "can_override": false}, "mass_crate_A": {"name": "mass_crate_A", "group": "Ungrouped variables", "definition": "random(30 .. 40#1)", "description": "", "templateType": "randrange", "can_override": false}, "mass_crate_B": {"name": "mass_crate_B", "group": "Ungrouped variables", "definition": "random(19 .. 25#1)", "description": "

Mass of Crate B (kg)

", "templateType": "randrange", "can_override": false}, "co_eff_A": {"name": "co_eff_A", "group": "Ungrouped variables", "definition": "random(0.15 .. 0.2#0.01)", "description": "", "templateType": "randrange", "can_override": false}, "Co_eff_B": {"name": "Co_eff_B", "group": "Ungrouped variables", "definition": "random(0.25 .. 0.32#0.01)", "description": "", "templateType": "randrange", "can_override": false}, "Theta_A": {"name": "Theta_A", "group": "Ungrouped variables", "definition": "degrees(arctan(co_eff_a))", "description": "", "templateType": "anything", "can_override": false}, "Theta_B": {"name": "Theta_B", "group": "Ungrouped variables", "definition": "degrees(arctan(co_eff_b))", "description": "", "templateType": "anything", "can_override": false}, "Weight_Crate_A": {"name": "Weight_Crate_A", "group": "Ungrouped variables", "definition": "mass_crate_a*acc_grav", "description": "

N

", "templateType": "anything", "can_override": false}, "Weight_Crate_B": {"name": "Weight_Crate_B", "group": "Ungrouped variables", "definition": "mass_crate_b*acc_grav", "description": "

N

", "templateType": "anything", "can_override": false}, "fric_A": {"name": "fric_A", "group": "Ungrouped variables", "definition": "weight_crate_a*co_eff_a", "description": "", "templateType": "anything", "can_override": false}, "fric_b": {"name": "fric_b", "group": "Ungrouped variables", "definition": "co_eff_b*weight_crate_b", "description": "", "templateType": "anything", "can_override": false}, "Theta_AB": {"name": "Theta_AB", "group": "Ungrouped variables", "definition": "degrees(Arctan((fric_a+fric_b)/(weight_crate_a+weight_crate_b)))", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Acc_Grav", "mass_crate_A", "mass_crate_B", "co_eff_A", "Co_eff_B", "Theta_A", "Theta_B", "Weight_Crate_A", "Weight_Crate_B", "fric_A", "fric_b", "Theta_AB"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) Calculate (to within 1 decimal place) the angle θ when Crate A begins to slide.

\n

[7 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part b) Calculate (to within 1 decimal place) the angle θ when Crate B begins to slide.

\n

[2 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part c) If the 2 masses are connected at points C & D by a cable.

\n

Calculate the angle (to within 1 decimal place) the two joined crates begin to slide.

\n

[6 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Ensure you include a free body diagram in your workings. 

\n

[5 Marks]

"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question"}, {"name": "MeQ4 - Kinematics - Randomised Variables Only", "extensions": [], "custom_part_types": [], "resources": [["question-resources/UWESbeMeCC1_Q4_-_Kinematics.png", "/srv/numbas/media/question-resources/UWESbeMeCC1_Q4_-_Kinematics.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}], "tags": [], "metadata": {"description": "

Rocket Launched to zenith

", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "

Kinematics

\n

At t0, a small rocket of mass {Rocket_Mass} kg is launched vertically from rest and it accelerates uniformly at {Rocket_Acc} ms-2 for a period of {Time_1} s, at which point all of the fuel is used(t1). 

\n

The rocket then continues to travel freely in the vertical direction until it eventually reaches its maximum altitude (t2), after which it falls to earth and impacts the ground at exactly the same height it was launched (t3).

\n

\"rocket

", "advice": "", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"Acc_Grav": {"name": "Acc_Grav", "group": "Ungrouped variables", "definition": "9.81", "description": "

Acceleration due to gravity.

", "templateType": "number", "can_override": false}, "Rocket_Acc": {"name": "Rocket_Acc", "group": "Ungrouped variables", "definition": "random(20 .. 25#1)", "description": "", "templateType": "randrange", "can_override": false}, "Rocket_Mass": {"name": "Rocket_Mass", "group": "Ungrouped variables", "definition": "random(40 .. 60#5)", "description": "", "templateType": "randrange", "can_override": false}, "Time_1": {"name": "Time_1", "group": "Ungrouped variables", "definition": "random(10 .. 15#1)", "description": "", "templateType": "randrange", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Acc_Grav", "Rocket_Acc", "Rocket_Mass", "Time_1"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) Calculate the rocket’s velocity at the instant (t1) when all of the fuel is used.

\n

[2 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part b) Calculate the altitude (m) at the instant (t1) when all of the fuel is used.

\n

[2Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part c) The time it takes to reach the maximum altitude.

\n

[4Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part d) The maximum altitude reached.

\n

[4 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part e) Its velocity at the instant (t3) just prior to impact with the ground.

\n

[3 Marks]

"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Ensure you indicate the relative kinematic values of the rocket on a diagram in your workings.

\n

[5 Marks]

"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "type": "question"}, {"name": "MeQ5 - Centre of Gravity - Randomised Variables Only", "extensions": [], "custom_part_types": [], "resources": [["question-resources/UWESbeMeCC1_Q5_-_Centre_of_Gravity.png", "/srv/numbas/media/question-resources/UWESbeMeCC1_Q5_-_Centre_of_Gravity.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}], "tags": [], "metadata": {"description": "

Determinig the CoG of a composite part

", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "

Centre of Gravity

\n

A component consists of 3 horizontal concentric solid cylinders, A, B & C fixed together as shown in the diagram.

\n

\"Component

\n

The dimensions and material properties are:

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\n

Cylinder

\n
\n

Material

\n
\n

Density ρ (kgm-3)

\n
\n

Diameter (mm)

\n
\n

Length (mm)

\n
\n

A

\n
\n

Aluminium Alloy

\n
\n

ρA

\n
\n

{Den_a}

\n
\n

dA

\n
\n

{Dia_a}

\n
\n

lA

\n
\n

{Len_a}

\n
\n

B

\n
\n

Copper Alloy

\n
\n

ρB

\n
\n

{Den_b}

\n
\n

dB

\n
\n

{Dia_b}

\n
\n

lB

\n
\n

{Len_b}

\n
\n

C

\n
\n

Steel

\n
\n

ρC

\n
\n

{Den_c}

\n
\n

dC

\n
\n

{Dia_c}

\n
\n

lC

\n
\n

{Len_c}

\n
\n

", "advice": "

.

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Part a) Calculate the total volume of the component.

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[4 Marks]

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Part b) Calculate the total mass of the component.

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[4 Marks]

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Part c) Calculate the total weight of the component.

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[2 Marks]

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Part d) Calculate the coordinate of the Centre of Gravity along its length.

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[5 Marks]

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Ensure you show the position of the CoG on a diagram in your workings.

\n

[5 Marks]

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Trolley on a slope

", "licence": "All rights reserved"}, "statement": "

Kinetic & Potential Energy

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A trolley of total mass {MeQ8_Trolley_mass} kg is being manoeuvred down a ramp with a {MeQ8_Angle_of_Slope}\u25e6 slope.  During this motion, the trolley experiences a rolling resistance to its motion of {MeQ8_RollingResistance} N.

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Whilst travelling at a velocity of {MeQ8_Trolley_v_Start} m/s, a braking force is applied, and the trolley is brought uniformly to rest in a distance (d) of {MeQ8_Distance_Travelled} m.  During this period of constant deceleration, it may be assumed that the rolling resistance remains constant, acting to assist the braking force.

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\"Trolley

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During the period that the trolley is slowing down, calculate the following:

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see spreadsheet

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Trolley total mass

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ramp slope.  

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resistance to its motion

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Trolley initial velocity

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trolley is brought uniformly to rest in a distance (d)

", "templateType": "randrange", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["MeQ8_Trolley_mass", "MeQ8_Angle_of_Slope", "MeQ8_RollingResistance", "MeQ8_Trolley_v_Start", "MeQ8_Distance_Travelled"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Part a) The vertical height descended & change in potential energy.

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[2 Marks]

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Part b) Its decrease in kinetic energy.

\n

[2 Marks]

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Part c) The work done against the rolling resistance.

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[2 Marks]

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Part d) The energy absorbed by the brakes.

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[3 Marks]

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Part e) The average braking force.

\n

[2 Marks]

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Part f) The deceleration.

\n

[2 Marks]

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Part g) The resultant decelerating force which acts on the truck parallel to the slope.

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[2 Marks]

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Ensure you include diagrams in your workings.

\n

[5 Marks]

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Instructions

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Ver 2.2

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This will not be used

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