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Transmission of Heat — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsTransmission of Heat1 Mark
Question
Assertion : All black coloured objects are considered black bodies.
Reason : Black colour is a good absorber of heat.
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Answer

(e) It is not necessary that all black coloured object are black bodies. For example, if we take a black surface which is highly polished, it will not behave as a perfect black body.A perfectly black body absorbs all the radiations incident on it.

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