Heat Transfer - Engineering

Q1:

In thermal radiation for a black body (where, ε is emissivity and α is absorptivity)

A α = 1; ε ≠ 1

B α ≠ 1, ε = 1

C α ≠ 1, ε ≠ 1

D α = 1; ε = 1

ANS:D - α = 1; ε = 1

In thermal radiation for a black body, both the absorptivity (α) and emissivity (ε) are equal to 1. So, the correct statement is: d) =1;=1α=1;ε=1