Black Body Properties – Rankers Physics

Heat Transfer - Radiation: Practice Problem & Solution

Assertion (A): For an ideal black body, both absorption coefficient and reflection coefficient are one. Reason (R): Perfect absorbers are perfect reflectors.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Heat Transfer - Radiation. Understanding the underlying formula is key to arriving at the correct answer below:

A black body is defined as a perfect absorber (absorption coefficient = 1) and a perfect emitter, but it reflects no radiation (reflection coefficient = \(0\)).

Perfect absorbers are the opposite of perfect reflectors. Both Assertion (A) and Reason (R) are false.

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