# A solenoid is connected to a direct current (d.c.) supply. Describe the magnetic field produced inside and outside the solenoid, and explain how the strength of this magnetic field can be increased.

> WJEC GCSE Physics (Wales) — 2.5 Magnetism and electromagnetism · Describe and Explain · 4 marks

## Mark scheme (4 marks)

1. The magnetic field inside the solenoid is uniform (parallel field lines along the axis)
2. The magnetic field outside the solenoid is similar to that of a bar magnet (with a north and south pole at each end)
3. Increasing the current in the solenoid increases the strength of the magnetic field
4. Increasing the number of turns (coils/loops) per unit length increases the strength of the magnetic field

## Key terms

- [solenoid](https://www.gradenine.co.uk/glossary/solenoid)
- [magnetic field](https://www.gradenine.co.uk/glossary/magnetic-field)
- [direct current](https://www.gradenine.co.uk/glossary/direct-current)

## Related

- [Revision notes for WJEC GCSE Physics (Wales)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe and 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-solenoid-is-connected-to-a-a799b4df) · Published by Druglandscape Ltd.