# Explain how crumple zones and seat belts work together to reduce the risk of injury to passengers during a car collision.

> Eduqas GCSE Physics — 4.3 Safety in public transport · Explain · 4 marks

## Mark scheme (4 marks)

1. Crumple zones increase the time (or distance) over which the car decelerates during a collision
2. A longer deceleration time means the force experienced by passengers is reduced (since force = change in momentum / time)
3. Seat belts prevent passengers from continuing to move forward (at the original speed) after the car has stopped
4. Seat belts also stretch slightly, increasing the time over which the passenger decelerates, further reducing the force on the passenger

## Key terms

- [crumple zones](https://www.gradenine.co.uk/glossary/crumple-zones)
- [seat belts](https://www.gradenine.co.uk/glossary/seat-belts)

## Related

- [Revision notes for Eduqas GCSE Physics](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/explain-how-crumple-zones-and-seat-ff423192) · Published by Druglandscape Ltd.