# A car travelling along a straight road accelerates uniformly from rest. Explain how the velocity–time graph for this motion differs from the displacement–time graph for the same motion, and what each graph reveals about the car's acceleration.

> IB DP Physics Standard Level (2023 syllabus) — A.1 Kinematics · Explain · 4 marks

## Mark scheme (4 marks)

1. The velocity–time graph is a straight line (through the origin) with a positive gradient
2. The displacement–time graph is a curve (parabola / increasing gradient) starting from the origin
3. The gradient of the velocity–time graph gives / equals the (uniform) acceleration
4. The gradient of the displacement–time graph increases with time, confirming the car is accelerating / non-zero acceleration; OR the acceleration equals the second derivative / rate of change of the gradient of the s–t graph

## Key terms

- [velocity–time graph](https://www.gradenine.co.uk/glossary/velocity-time-graph)
- [displacement–time graph](https://www.gradenine.co.uk/glossary/displacement-time-graph)

## Related

- [Revision notes for IB DP Physics Standard Level (2023 syllabus)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-car-travelling-along-a-straight-8ae0d313) · Published by Druglandscape Ltd.