# A wind turbine generates electricity for a remote village. The turbine blades spin a coil of wire between two permanent magnets. The electricity produced is then passed through a transformer before being distributed to homes. Explain how the turbine generates electricity and why a transformer is needed before the electricity reaches the homes.

> OCR A-Level Physics A (H556) — 4.5 Quantum physics · Explain · 5 marks

> Wind turbines use the generator effect to produce electricity. The voltage produced by the turbine is relatively low compared to the voltage used to distribute electricity efficiently.

## Mark scheme (5 marks)

1. The spinning coil of wire moves relative to the magnetic field (or the coil cuts through magnetic field lines)
2. A potential difference is induced across the ends of the coil (generator effect)
3. Because the coil is part of a complete circuit, an alternating current flows
4. A step-up transformer increases the voltage (potential difference) for distribution
5. Transmitting electricity at higher voltage reduces energy loss, making distribution more efficient

## Related

- [Revision notes for OCR A-Level Physics A (H556)](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-wind-turbine-generates-electricity-for-6d76e437) · Published by Druglandscape Ltd.