# A cyclist travelling at high speed collides with a stationary bollard and comes to a sudden stop. Explain why a cyclist wearing a padded jacket is less likely to suffer serious injury than a cyclist wearing no padding, even though both cyclists experience the same change in momentum.

> Pearson Edexcel International GCSE Physics (4PH1) — 1.3 Forces, movement, shape and momentum · Explain · 4 marks

> Padded cycling jackets contain thick foam layers that compress during an impact. Without padding, the cyclist's body stops almost instantly on contact with the bollard.

## Mark scheme (4 marks)

1. The padded jacket increases the time over which the cyclist's momentum changes (comes to rest)
2. The change in momentum is the same for both cyclists
3. Force equals the rate of change of momentum (change in momentum divided by time)
4. Therefore, the padded jacket reduces the force experienced by the cyclist, reducing the risk of injury

## Key terms

- [momentum](https://www.gradenine.co.uk/glossary/momentum)
- [change in momentum](https://www.gradenine.co.uk/glossary/change-in-momentum)

## Related

- [Revision notes for Pearson Edexcel International GCSE Physics (4PH1)](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-travelling-at-high-speed-1ade5f24) · Published by Druglandscape Ltd.