AQA GCSE Physics Physics Paper 1 (Foundation), June 2022: Question 2
8 marks · Standard Demand difficulty · Short Answer
Calculate the gravitational potential energy, power, and kinetic energy involved when a girl and a boy run up stairs, and identify measuring instruments.
Practise this questionQuestion
Question text
02 A girl ran to the top of some stairs.
Figure 2 shows the stairs.
Figure 2
02.1 The girl measured the height of the stairs.
What measuring instrument should she have used?
[1 mark]
02.2 The height of the stairs was 1.7 m.
The mass of the girl was 50 kg.
gravitational field strength = 9.8 N/kg
Calculate the change in gravitational potential energy of the girl.
Use the equation:
gravitational potential energy = mass × gravitational field strength × height
[2 marks]
Gravitational potential energy =6 J
02.3 A boy ran up the same stairs and did 1800 J of work.
The time it took the boy to run up the stairs was 1.44 s.
Calculate the power of the boy.
Use the equation:
work done
power =
time
[2 marks]
Power = W
02.4 Which stop-clock was used to measure the time the boy took to run up the stairs?
[1 mark]
Tick ( ) one box.
Stop-clock A Stop-clock B Stop-clock C
02.5 The boy had a speed of 2.0 m/s at the top of the stairs.
The mass of the boy was 70 kg.
Calculate the kinetic energy of the boy at the top of the stairs.
Use the equation:
kinetic energy = 0.5 × mass × (speed)2
[2 marks]
Kinetic energy = J
Mark scheme
Show the mark scheme
Question 2
AO /
Question Answers Extra information Mark
Spec. Ref.
02.1 tape measure 1 AO3
or 4.1.1.4
metre rule allow ruler
ignore metre stick
AO /
Spec. Ref.
02.2 Ep = 50 × 9.8 × 1.7 1 AO2
4.1.1.2
Ep = 833 (J) 1
AO /
Spec. Ref.
02.3 1800 1 AO2
P = 4.1.1.4
1.44
P = 1250 (W) 1
AO /
Spec. Ref.
02.4 stop-clock C 1 AO3
– HYSICS – – 4.1.1.4
AO /
Spec. Ref.
02.5 E = 0.5 × 70 × 2.02 1 AO2
k
4.1.2.1
Ek = 140 (J) 1
Total Question 2 8
How to answer it
Energy, Power, and Measurements Study Guide
What this question tests
This question assesses your practical selection skills (measuring instruments and reading resolutions) alongside core energy calculations. You will need to recall and apply equations for gravitational potential energy (Ep), kinetic energy (Ek), and power, while ensuring proper substitution and unit usage.
Measuring Height
✅ Correct Answer
Tape measure or metre rule
💡 Key Knowledge
- For large vertical distances like stairs, a standard ruler is too small.
- A tape measure or metre rule provides the correct scale and range for measuring human-scale heights.
🧠 Exam Technique
Keep your answer concise. Do not add unnecessary adjectives. The mark scheme also accepts "ruler" but strictly ignores "metre stick".
Calculating Gravitational Potential Energy
✅ Correct Answer
Ep = 833 J
📐 Step-by-Step Calculation
- State the equation: Ep = mass × gravitational field strength × height
- Substitute values: Ep = 50 × 9.8 × 1.7
- Calculate final value: Ep = 833
❌ Common Errors
A common mistake is forgetting to include the correct unit (Joules, J ) or incorrectly transcribing numbers from the prompt. Always double-check your calculator entries.
Calculating Power
✅ Correct Answer
Power = 1250 W
📐 Step-by-Step Calculation
- State the equation: power = work done / time
- Substitute values: P = 1800 / 1.44
- Calculate final value: P = 1250
💡 Key Knowledge
Power is the rate at which energy is transferred or work is done. Its unit is Watts ( W ) or Joules per second ( J/s ).
Selecting the Correct Stop-Clock
✅ Correct Answer
Stop-clock C
💡 Key Knowledge
Look closely at the digital displays:
- Stop-clock A: reads to 0.1 s (tenths of a second)
- Stop-clock B: analogue clock measuring up to 60 seconds
- Stop-clock C: reads to 0.01 s (hundredths of a second)
❌ Common Errors
Students often mistake Stop-clock A for C because they don't check the decimal places on the digital screen. The time given in the previous question (1.44 s) requires a stop-clock capable of measuring to hundredths of a second.
Calculating Kinetic Energy
✅ Correct Answer
Kinetic energy = 140 J
📐 Step-by-Step Calculation
- State the equation: kinetic energy = 0.5 × mass × speed²
- Substitute values: Ek = 0.5 × 70 × (2.0)²
- Square the speed first: 2.0² = 4.0
- Calculate final value: Ek = 0.5 × 70 × 4 = 140
❌ Common Errors
The Squaring Trap: Students frequently forget to square the velocity term, multiplying 0.5 × mass × speed instead. Always write out the squared term clearly in your working out!
Topics
Physics · P1: Energy · P5: Forces
Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 1 (Foundation), June 2022. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.