# A student sets up a simple electric bell. Inside the bell, an electromagnet is used to make a metal striker hit the bell repeatedly as long as the switch is pressed. Explain why the striker moves towards the electromagnet when the switch is pressed, and why it then moves away again, allowing the bell to ring continuously.

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

> An electric bell contains an electromagnet connected in series with a springy metal strip and a contact screw. When the circuit is complete, the electromagnet pulls the metal strip towards it. As the strip moves, it breaks the circuit at the contact screw.

## Mark scheme (4 marks)

1. When the switch is pressed, current flows through the coil, creating a magnetic field / making the coil magnetic
2. The electromagnet attracts the iron/metal striker/strip, pulling it towards the coil
3. As the striker moves, the circuit is broken (contact is lost at the screw), so the current stops flowing
4. With no current, the electromagnet loses its magnetism, so the springy strip returns to its original position, completing the circuit again / allowing the cycle to repeat

## Key terms

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

## 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-sets-up-a-simple-b267bd96) · Published by Druglandscape Ltd.