Answer to Question #229282 in Molecular Physics | Thermodynamics for Ebrahim

Question

What is a black body?what are the characteristics of a black body radiation? How has the idea of a black body been achieved in practice?

Answer 1

A blackbody is an object that absorbs all the radiation that falls on it including visible light$.$

The radiation emitted by a black body does not depend on the direction of the source and does not determine the amount of radiation emitted. Also, the only external factor that black body radiation depends on temperature.

Examples of real practical black bodies include platinum black and also lamp black which come close to being ideal black bodies.

It should be noted that these can only absorb up to 96% of the incident radiation and so are not perfect black objects.