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Assertion : A body that is a good radiat...

Assertion : A body that is a good radiator is also a good absorber of radiation at a given wavelength.
Reason : According to Kirchhoff's law the absorptivity of a body is equal to its emissivity at a given wavelength

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If both assertion and reason are false

Text Solution

Verified by Experts

The correct Answer is:
A
According to Kirchhoff's law, a=e. or the absorptivity of a body equals its emissivity. A good absorber is a good emitter. As a good absorber is poor reflector, emitting (or radiating) ability of body is oppositely related to its ability to reflect. Therefore good emitter (or radiator) is a poor reflector.
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