# A family is trying to reduce the amount of energy they use at home. They notice that their electric kettle has a higher power-rating than their slow cooker. Explain what power-rating means and describe how an appliance with a higher power-rating affects the cost of running it for the same amount of time.

> WJEC GCSE Physics (Wales) — 1.4 Domestic electricity · Explain · 4 marks

> An electric kettle has a power-rating of 3 kW. A slow cooker has a power-rating of 0.3 kW.

## Mark scheme (4 marks)

1. Power-rating is the maximum rate of energy transfer of an appliance
2. A higher power-rating means more energy is transferred per second / in a given time
3. More energy used in the same time means a greater number of kilowatt-hours are consumed
4. Therefore the appliance with the higher power-rating costs more to run for the same amount of time

## Key terms

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

## Related

- [Revision notes for WJEC GCSE Physics (Wales)](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-family-is-trying-to-reduce-4e713ce2) · Published by Druglandscape Ltd.