AQA GCSE Physics Physics Paper 1 (Foundation), June 2023: Question 6
8 marks · Low Demand difficulty · Short Answer
Compare energy stores during a bungee jump, calculate the elastic potential energy stored in a stretched bungee cord, and evaluate cords based on spring constant and maximum extension.
Practise this questionQuestion
Question text
06 Figure 8 shows a student before and during a bungee jump.
The diagram is not to scale.
Figure 8
06.1 In position B, the student is moving towards the river and the bungee cord
is stretching.
How do the energy stores in position B compare with the energy stores in position A?
[3 marks]
Tick ( ) one box in each row.
Less than The same More than
Energy store
at A as at A at A
The student’s gravitational
potential energy
The student’s kinetic energy
The bungee cord’s elastic
potential energy 26
06.2 The bungee cord behaves like a spring with a spring constant of 78.4 N/m.
At one point in the bungee jump, the extension of the bungee cord is 25 m.
*25* Calculate the elastic potential energy stored by the bungee cord.
Use the equation:
elastic potential energy = 0.5 × spring constant × extension2
[2 marks]
Elastic potential energy = J
Table 5 shows information about different bungee cords.
Table 5
Maximum extension
Spring constant
Bungee cord before snapping
in N/m
in metres
A 78.4 36
B 82.0 24
C 84.5 12
06.3 Bungee cord C will have a smaller extension than A or B for any bungee jumper.
Give the reason why.
[1 mark]
06.4 Which bungee cord would be safest to use for a person with a large weight?
Give a reason for your answer.
*26* [2 marks]
Bungee cord
Reason
Mark scheme
Show the mark scheme
Question 6
AO /
Question Answers Mark
Spec. Ref.
06.1 AO1
4.1.1.1
Energy store Less The More
than at A same as than at A
at A
The student’s
gravitational potential ✓
energy
The student’s kinetic
✓ 1
energy
The bungee cord’s
✓ 1
elastic potential energy
additional tick in a row negates the mark for that row
AO /
Question Answers Extra information Mark
Spec. Ref.
06.2 E = 0.5 × 78.4 × 252 1 AO2
e
4.1.1.2
Ee = 24 500 (J) 1
AO /
Spec. Ref.
06.3 greatest spring constant allow needs largest force (per 1 AO3
metre) to stretch the cord–HYSICS – – 4.1.1.2
AO /
Spec. Ref.
06.4 A 1 AO3
4.1.1.2
greatest extension before MP2 dependent on scoring MP1 1
snapping
Total Question 6 8
How to answer it
Energy Changes and Hooke's Law in a Bungee Jump
What this question tests
This question assesses your understanding of energy stores (gravitational potential, kinetic, and elastic potential) during motion, calculating elastic potential energy using an equation, interpreting spring constants, and evaluating experimental data to assess physical safety.
Comparing Energy Stores During a Jump
Identifying changes in GPE, KE, and EPE as the student falls
✅ Correct Answer (Table Completion)
| Energy store | Tick (✓) Choice |
|---|---|
| Gravitational potential energy | Less than at A [1 mark] |
| Kinetic energy | More than at A [1 mark] |
| Elastic potential energy | More than at A [1 mark] |
💡 Key Knowledge
- Gravitational Potential Energy (GPE): Depends on vertical height ( Ep = mgh ). At position B, the student is lower down, so GPE has decreased.
- Kinetic Energy (KE): Depends on speed ( Ek = ½mv² ). At A, the jumper was stationary (KE = 0). At B, they are moving downwards, so KE has increased.
- Elastic Potential Energy (EPE): Stored when stretched ( Ee = ½ke² ). The cord was unstretched at A and is stretching at B, so EPE has increased.
🧠 Exam Technique
Read the question prompt carefully: "in position B, the student is moving towards the river and the bungee cord is stretching".
- "Moving" immediately tells you speed > 0, so kinetic energy must be greater than at rest.
- "Stretching" means extension > 0, so elastic potential energy must be greater than unstretched.
❌ Common Errors
- Multiple ticks: Ticking more than one box in a row cancels out (negates) the mark for that row.
- Assuming total GPE becomes zero: The student is lower, but not necessarily at ground level—focus on whether it is less or more relative to A.
Calculating Elastic Potential Energy
Applying the equation: Ee = 0.5 × spring constant × extension²
📐 Step-by-Step Calculation
- Identify the given values:
Spring constant ( k ) = 78.4 N/m
Extension ( e ) = 25 m - Substitute into the formula:
Ee = 0.5 × 78.4 × 25² [1 mark] - Calculate extension squared:
25² = 625 - Complete the multiplication:
Ee = 0.5 × 78.4 × 625 = 24 500 J [1 mark]
🧠 Exam Technique: Squaring First
The equation is provided on the paper. Always write down the full substitution before typing it into your calculator.
Entering 0.5 × 78.4 × 25² directly into a scientific calculator handles order of operations (BIDMAS) automatically.
❌ Common Errors
- Forgetting to square the extension: Doing 0.5 × 78.4 × 25 = 980 J is the single most common mistake on this question.
- Squaring the whole product: Squaring (0.5 × 78.4 × 25)² instead of only the extension ( 25² ).
Understanding Spring Constant
Explaining why Cord C has a smaller extension than A or B
✅ Correct Answer
It has the greatest spring constant [1 mark].
💡 Key Knowledge
- Spring Constant ( k ): A measure of the stiffness of a spring or cord. It tells you the force required to stretch it by 1 metre ( F = k × e ).
- A higher spring constant means the cord is stiffer and extends less for a given force or weight.
- From Table 5: Cord C has k = 84.5 N/m , which is greater than A (78.4) and B (82.0).
❌ Common Errors
- Confusing extension limit with stiffness: Quoting the "12 m maximum extension" does not explain why it stretches less for a given load.
- Vague descriptions: Writing "it is stronger" or "it is thicker" without mentioning spring constant or force per metre will not score the mark.
Evaluating Cord Safety for a Heavier Person
Selecting the safest cord and providing evidence from the data
✅ Correct Answer
Bungee cord: A [1 mark]
Reason: It has the greatest extension before snapping (36 m) [1 mark].
💡 Key Knowledge & Reasoning
- A person with a large weight exerts a much larger downward force and starts with more gravitational potential energy.
- This causes the cord to stretch significantly further during the jump.
- Cord A can stretch up to 36 m before snapping, making it the least likely to snap under a heavy load. In comparison, Cord C snaps at just 12 m.
🧠 Exam Technique: Two-Part Reasoning
Always match the cord choice explicitly with the data table column heading. The column states "Maximum extension before snapping", so your reason must reference snapping / maximum extension rather than repeating general terms like "it's safer".
❌ Common Errors
- Picking Cord C: Students mistakenly pick C thinking a "higher spring constant" makes it safer or stronger, ignoring that C snaps at only 12 m extension!
- Missing comparative language: Writing "it stretches 36 m" without stating that this is the maximum or greatest value before failure.
Topics
Physics · P1: Energy · P5: Forces
Question and mark scheme from the AQA GCSE Physics examination, Physics Paper 1 (Foundation), June 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.