# Describe how the temperature of a perfect black body affects the radiation it emits.

> AQA GCSE Physics (8463) — 4.6.3 Black body radiation (Phys only) · Describe · 4 marks

> A metal sphere is heated in a furnace. At low temperatures it appears dull and dark. As its temperature rises, it begins to glow.

## Mark scheme (4 marks)

1. A perfect black body absorbs all radiation incident on it (and does not reflect or transmit any radiation)
2. The hotter the object, the greater the infrared radiation emitted in a given time
3. As temperature increases, the peak of the emitted radiation shifts to shorter wavelengths (higher frequencies)
4. A body at constant temperature emits radiation at the same rate as it absorbs radiation

## Key terms

- [perfect black body](https://www.gradenine.co.uk/glossary/perfect-black-body)

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Source: [GradeNine](https://www.gradenine.co.uk/q/describe-how-the-temperature-of-a-85b715fc) · Published by Druglandscape Ltd.