Temperature
Physics: AQA GCSE Higher, topic 6.6.4
Temperature and Black Bodies
All bodies (objects) emit radiation. The temperature of a body (object) is linked to the intensity (rate) and wavelength of the emitted radiation. Black bodies are perfect absorbers and emitters of radiation - they never reflect or transmit radiation.
Constant temperature
- A body at constant temperature absorbs radiation at the same rate that it emits radiation.
Changing temperature
- An object will always transmit (send) heat from a hotter area to a colder area.
- Radiators work based on this principle.
- This means that when an object’s internal temperature is higher than the temperature of the environment around it, the rate of emission will be higher than if the object were in a warmer environment.
Test yourself on Temperature
When does an object emit radiation faster?
Which of these is a property of a perfect black body?