# A student places a soft iron bar inside a solenoid connected to a battery. Explain why the soft iron bar becomes a magnet when the current is switched on, and describe what happens to the magnetism of the soft iron bar when the current is switched off.

> WJEC A-Level Physics (Wales) — 4.4 Magnetic fields · Explain · 5 marks

## Mark scheme (5 marks)

1. The solenoid carrying a current produces a magnetic field (inside the coil)
2. The magnetic field of the solenoid magnetises the soft iron bar / causes the soft iron bar to become a magnet
3. Soft iron is a magnetically soft material, meaning it is easy to magnetise
4. When the current is switched off, the magnetic field of the solenoid disappears
5. The soft iron bar loses its magnetism (almost immediately) when the current is switched off, because it is a magnetically soft material

## Key terms

- [solenoid](https://www.gradenine.co.uk/glossary/solenoid)
- [soft iron](https://www.gradenine.co.uk/glossary/soft-iron)

## Related

- [Revision notes for WJEC A-Level Physics (Wales)](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-soft-iron-15fd7d53) · Published by Druglandscape Ltd.