# A rescue worker uses an electromagnet attached to a crane to separate iron and steel objects from non-magnetic waste at a recycling centre. The electromagnet stops working effectively and the worker decides to improve it. Describe five ways the worker could increase the strength of the magnetic field produced by the electromagnet.

> OCR A-Level Physics A (H556) — 4.4 Waves · Describe · 5 marks

> An electromagnet consists of a solenoid with an iron core. The strength of its magnetic field depends on several factors related to the coil and the current flowing through it.

## Mark scheme (5 marks)

1. Increase the size (magnitude) of the current flowing through the coil
2. Increase the number of turns (coils) of wire
3. Increase the length of the coil / solenoid
4. Increase the cross-sectional area of the coil
5. Use an iron core inside the solenoid (or replace a non-iron core with iron)

## Key terms

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

## Related

- [Revision notes for OCR A-Level Physics A (H556)](https://www.gradenine.co.uk/learn)
- [How to answer "Describe" 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-rescue-worker-uses-an-electromagnet-73dee68b) · Published by Druglandscape Ltd.