# A cyclist travels along a flat road and then up a steep hill before stopping at the top. Explain how the concepts of scalar and vector quantities apply to the cyclist's motion during this journey, and describe what the velocity-time graph of this journey would show about the cyclist's acceleration.

> OCR A-Level Physics B: Advancing Physics (H557) — 2.1 Physical quantities and units · Explain · 5 marks

> A cyclist starts from rest, accelerates along a flat road, then decelerates as they climb a steep hill, eventually coming to a stop at the top of the hill.

## Mark scheme (5 marks)

1. Distance is a scalar quantity — it has magnitude only / does not depend on direction
2. Displacement is a vector quantity — it has both magnitude and direction / is the straight line between starting and finishing points
3. Velocity is a vector quantity — it gives speed in a given direction / speed is scalar but velocity is vector
4. On the velocity-time graph, a positive gradient during the flat section shows the cyclist is accelerating (velocity is increasing)
5. A negative gradient on the velocity-time graph during the hill section shows the cyclist is decelerating / slowing down until velocity reaches zero

## Key terms

- [scalar](https://www.gradenine.co.uk/glossary/scalar)
- [vector](https://www.gradenine.co.uk/glossary/vector)
- [velocity](https://www.gradenine.co.uk/glossary/velocity)
- [acceleration](https://www.gradenine.co.uk/glossary/acceleration)

## Related

- [Revision notes for OCR A-Level Physics B: Advancing Physics (H557)](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-cyclist-travels-along-a-flat-15e56b36) · Published by Druglandscape Ltd.