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Heat radiation

Heat radiation is invisible to the human eye but the radiation from hot bodies can be felt by your hand. The proper name for heat radiation is INFRA RED RADIATION.

All objects emit heat radiation. If we take two objects of the same material and the same size but at different temperatures the one which is hotter will emit more radiation.

Two objects of the same material and the same temperature but of different sizes emit different amounts of heat radiation – the bigger one emitting more radiation than the smaller one.

Heat radiation experiments show that:

Black surfaces are the best emitters of heat radiation.
Black surfaces are the best absorbers of heat radiation.
Shiny surfaces are the best reflectors of heat radiation.
Shiny surfaces are poor absorbers of heat radiation.
Glass will not transmit heat radiation.
 
 
 
© Keith Gibbs 2011