# A fuse and a circuit breaker can both be used as safety devices in mains electrical appliances. Explain how a fuse protects an appliance when the current becomes too high, and state two advantages of using a circuit breaker instead of a fuse.

> Pearson Edexcel International GCSE Physics (4PH1) — 2.1 Mains electricity · Explain · 4 marks

## Mark scheme (4 marks)

1. A fuse contains a thin metal wire/filament that melts/breaks when the current exceeds its rating
2. This breaks/disconnects the circuit, cutting off the current/power supply to the appliance
3. A circuit breaker can be reset and used again (whereas a fuse must be replaced)
4. A circuit breaker operates/acts faster than a fuse

## Key terms

- [fuse](https://www.gradenine.co.uk/glossary/fuse)
- [circuit breaker](https://www.gradenine.co.uk/glossary/circuit-breaker)
- [current](https://www.gradenine.co.uk/glossary/current)

## 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-fuse-and-a-circuit-breaker-c9f74b2d) · Published by Druglandscape Ltd.