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If the absorption coefficient and reflec...

If the absorption coefficient and reflection coefficient of a surface of a body are `0.4` and `0.6` respectively then:-

A

(a)Emissive power will be `0.2`

B

(b)Transmission power will be `0.2`

C

(c)Body will be be totally transparent

D

(d)Body will be totally opaque.

Text Solution

Verified by Experts

The correct Answer is:
D
For a grey body
` a + r +t = 1 ` if `alpha =0.4 ,r= 0.6`
then ` t=1-0.4 - 0.6 = 0`
The body is opaque
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