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Absorbing and emitting powers of a body ...

Absorbing and emitting powers of a body are 10 and 8 respectively. Then (Ideal Black Body) IBB emissivity will be . . . . .

A

`0.2`

B

`0.4`

C

`0.6`

D

`0.8`

Text Solution

Verified by Experts

The correct Answer is:
D
A constant temperature, all surface have equal absorbing and emitting power and their ratio is equal to absorptivity of (perfect) ideal black body. i.e. `(e)/(a)=epsilon`
Here, `e=8,a=10`
`:.epsilon=e/a`
`=(8)/(10)`
`=0.8`
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