# A fault occurs in the National Grid and all step-down transformers stop working. Explain what effect this would have on consumers and why this effect occurs.

> AQA GCSE Physics (8463) — 4.2.5 The National Grid · Explain · 4 marks

## Mark scheme (4 marks)

1. Consumers would receive electrical power at a very high potential difference (from the transmission cables)
2. Step-down transformers normally decrease/reduce the potential difference to safe, usable levels
3. The high potential difference would be dangerous / unsafe for consumers
4. Appliances are designed to operate at 230 V (mains supply), so the high potential difference would damage them / they would not function correctly

## Key terms

- [step-down transformers](https://www.gradenine.co.uk/glossary/step-down-transformers)
- [National Grid](https://www.gradenine.co.uk/glossary/national-grid)
- [consumers](https://www.gradenine.co.uk/glossary/consumers)

## Related

- [Revision notes for AQA GCSE Physics (8463)](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)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/a-fault-occurs-in-the-national-2cfcfec0) · Published by Druglandscape Ltd.