# A wind farm is connected to the National Grid. Describe how electricity generated by the wind farm is made suitable for transmission through power cables across the National Grid, and explain why this process is necessary.

> Eduqas GCSE Physics — 1.2 Generating electricity · Describe and Explain · 4 marks

## Mark scheme (4 marks)

1. A transformer is used to increase (step up) the voltage of the electricity from the wind farm.
2. Increasing the voltage reduces the current in the power cables.
3. A lower current reduces the energy loss (as heat) in the power cables, making transmission more efficient.
4. A step-down transformer is used at the end of transmission to reduce the voltage to a safe level for domestic/household use.

## Key terms

- [National Grid](https://www.gradenine.co.uk/glossary/national-grid)
- [power cables](https://www.gradenine.co.uk/glossary/power-cables)

## Related

- [Revision notes for Eduqas GCSE Physics](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-wind-farm-is-connected-to-c96380f9) · Published by Druglandscape Ltd.