Ncert Solutions Chemistry Class 11th Chemistry Class 11th Structure of Atoms

Define a black body. Does a complete black body exist practically?

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alok kumar singh | Contributor-Level 10

3 months ago

An ideal body, which emits and absorbs radiations of all frequencies uniformly, is called a black body and the radiation emitted by such a body is called black body radiation. In practice, no such body exists. Carbon black approximates fairly closely to black body. A good physical approximation to a black body is a cavity with a tiny hole, which has no other opening. Any ray entering the hole will be reflected by the cavity walls and will be eventually absorbed by the walls.

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