# A student notices that the cable connecting a lamp to the mains socket has become frayed, exposing the live wire inside. Explain why touching the exposed live wire is dangerous, and describe the role of the circuit breaker in protecting the student if a fault occurs.

> Eduqas GCSE Physics — 7.4 Domestic uses and safety · Explain · 4 marks

## Mark scheme (4 marks)

1. The live wire is at a high (alternating) voltage / 230 V
2. Touching the live wire allows current to flow through the body to earth, causing an electric shock
3. If a fault causes too large a current, the circuit breaker detects this and switches the circuit off / breaks the circuit
4. The circuit breaker can be reset and used again, making it more convenient than a fuse

## Key terms

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

## 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/a-student-notices-that-the-cable-b8b5e95f) · Published by Druglandscape Ltd.