AQA AS Level Physics Paper 2, June 2023: Question 34

1 mark · Easy difficulty · Multiple Choice

Identify what the shaded area under the force-distance graph for a proton and a neutron represents.

Practise this question

Question

A multiple choice question with a graph showing the variation of force in 10^4 N against distance in fm between a proton and a neutron. A curve shows repulsive force at very short distances, crossing zero at around 0.8 fm, and an attractive well reaching a minimum around 1.0 to 1.1 fm before tending to zero at larger distances; the region beneath the curve into the attractive zone is shaded. Below the graph, multiple-choice options A (acceleration), B (impulse), C (rate of change of kinetic energy), and D (work done) are listed with selection checkboxes.
Question text

34 The graph shows the variation of force with distance between a proton and a neutron.

The shaded area represents

[1 mark]

A acceleration.

B impulse.

C rate of change of kinetic energy.

D work done.

Mark scheme

Show the mark scheme Mark scheme indicating the correct answer is D, corresponding to work done.

34 D work done.

How to answer it

Force-Distance Graph and Work Done

What this question tests

This question tests your understanding of graphical analysis in physics—specifically, interpreting the physical significance of the area under a force-distance graph. It links nuclear physics (the strong nuclear force between a proton and a neutron) with fundamental mechanics concepts like work done.

Question Part 3.4

Interpreting Graphical Areas

✅ Correct Answer

D: work done.

Awarded 1 mark for selecting option D.

💡 Key Knowledge

  • The formula for work done by a variable force over a displacement is W = ∫ F dx .
  • On a graph of Force ( F ) on the y-axis against distance ( x ) on the x-axis, the area under the curve represents the product of force and distance (or displacement), which equates to work done.
  • The strong nuclear force curve shows an attractive region (negative force values below the axis) between approximately 0.8 fm and 2.5 fm.

🧠 Exam Technique

Always check the axis labels first! Y-axis is force and X-axis is distance . Multiplying the units together (Newtons × metres) gives Joules, which is the unit of work done or energy. This dimensional analysis is a quick way to verify graphical interpretations in multiple-choice questions.

❌ Common Errors

  • Impulse (B): Students often confuse area under a graph with impulse. However, impulse is the area under a force-time graph ( F × t ), not a force-distance graph.
  • Acceleration (A): Mistaking graphical area for kinematic quantities without considering dimensional units.

Topics

Physics · 3.2 Particles and radiation · 3.4 Mechanics and materials

Question and mark scheme from the AQA AS Level Physics examination, Paper 2, June 2023. QuestionVault is an independent revision resource; questions remain the copyright of the awarding body.