From a student

If you see the link below it is a test by someone proving that a black car is hotter than a white car. is it not true that the emissivity of paint is the same regardless of colour? this has confused me big time.

if the emissivity is the same with paint can this still affect temperatures?

http://www.tom-morrow-land.com/tests/cartemp/index.htm

Reply;

Yes the emissivity is the same for black and white paint.

Heat transfer through thermal radiation as a result of an objects temperature occurs throughout the infrared, visual and in part of the ultraviolet region. In the infrared there is no difference in the amount absorbed. In the visual region the black car will absorb more than the white one, due to the difference in the solar absorption in the visual region. If both cars were placed in a darkened room and exposed only to infrared radiation, there would be no difference in the amount of radiation absorbed.

 

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