# A refrigerator is plugged into the mains electricity supply. It keeps food cold by transferring thermal energy from inside the refrigerator to the room. Explain why the room temperature increases over time when a refrigerator is running, even though the refrigerator is removing heat from inside it.

> Eduqas GCSE Physics — 1.6 Distance, speed and acceleration · Explain · 4 marks

> A refrigerator has a power rating of 150 W. It is left running in a kitchen with all windows and doors closed.

## Mark scheme (4 marks)

1. The refrigerator transfers electrical energy from the mains supply into the system
2. Not all energy transferred is useful — some is wasted / the refrigerator is not 100% efficient
3. The total energy released into the room (heat removed from food + waste energy) is greater than the heat removed from inside
4. By conservation of energy, the total energy in the closed kitchen increases, so room temperature rises

## 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-refrigerator-is-plugged-into-the-821522ed) · Published by Druglandscape Ltd.