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These question consists of two statement...

These question consists of two statements each printed as Assertion and Reason. While answering these question you are required to choose any one of the following five responses.
Assertion: A body that is a good radiator is also a good absorber of radiation at a given wavelength.
Reason: According to Kirchoff's law, hte absorptivity of a body is equal to the 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

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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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