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

Solution Explained:

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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