A black body is defined as an object which
(A) looks black.
(B) absorbs all e-m radiation equally.
(C) absorbs all e-m radiation completely.
(D) reflects all e-m radiation.
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What this question is about
A black body is defined as an object which
(A) looks black. --- No.
Absorbing all visible light is not enough.
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A black body is defined as an object which
(B) absorbs all e-m radiation equally.
No. That would be a grey body.
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A black body is defined as an object which
(C) absorbs all e-m radiation completely.
Yes. Like a hole in a very large box.
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A black body is defined as an object which
(D) reflects all e-m radiation.
No. That would be a white body.
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