When absorptivity (α) = 1, reflectivity (ρ) = 0 and transmissivity (τ) = 0, then the body is said to be a
A. Black body
B. Grey body
C. Opaque body
D. White body
Answer: Option A
Solution (By Examveda Team)
A blackbody surface completely absorbs external irradiation, regardless of direction and wavelength distribution. Its surface absorptivity is always 1, so αλ = α = 1. The reflectivity of a blackbody is always zero.This Question Belongs to Mechanical Engineering >> Heat And Mass Transfer
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