# A car is travelling at constant speed along a motorway when the driver sees a warning sign and must stop the vehicle. Explain all the factors that affect the total stopping distance of the car.

> Eduqas A-Level Physics — 4.2 Kinetic theory and gases (A-Level only) · Explain · 5 marks

> Stopping distance is made up of thinking distance and braking distance.

## Mark scheme (5 marks)

1. Stopping distance is the sum of thinking distance and braking distance
2. Thinking distance is affected by the driver's reaction time / factors that increase reaction time (e.g. tiredness, drugs, alcohol)
3. Greater speed increases thinking distance (the vehicle travels further during the reaction time)
4. Braking distance is affected by adverse road or weather conditions (e.g. wet or icy roads reduce grip / friction)
5. Braking distance is affected by the condition of the vehicle (e.g. worn tyres or brakes)

## Key terms

- [stopping distance](https://www.gradenine.co.uk/glossary/stopping-distance)

## Related

- [Revision notes for Eduqas A-Level 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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/a-car-is-travelling-at-constant-4c8ab9ee) · Published by Druglandscape Ltd.