In thermal radiation for a black body (where is emissivity and...

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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

Answer: Option D

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