# A student places a magnetic compass near a current-carrying wire. When the current is switched on, the compass needle deflects. Explain why the needle deflects, and describe what happens to the deflection if the current in the wire is increased.

> Eduqas GCSE Physics — 2.5 Magnetism and electromagnetism · Explain · 4 marks

> A straight wire is connected to a battery and a switch. A small magnetic compass is placed a few centimetres from the wire.

## Mark scheme (4 marks)

1. A current flowing through a wire produces a magnetic field around the wire
2. The magnetic field of the wire exerts a force on the compass needle / interacts with the compass needle's own magnetic field
3. Increasing the current increases the strength of the magnetic field produced by the wire
4. A stronger magnetic field causes a greater deflection of the compass needle

## Key terms

- [current](https://www.gradenine.co.uk/glossary/current)
- [deflection](https://www.gradenine.co.uk/glossary/deflection)
- [compass needle](https://www.gradenine.co.uk/glossary/compass-needle)

## 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-places-a-magnetic-compass-de581f5b) · Published by Druglandscape Ltd.