A body, which emits radiations of all possible wavelengths, is known as
A
Good conductor
B
Partial radiator
C
Absorber of photons
D
Perfectly black-body
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D
Perfectly black-body
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$Assertion :$ A body that is 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.
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