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A black body emit heat at the rate of 20...

A black body emit heat at the rate of `20 W`, when its tempertaure is `227^(@)C` Another black body emits heat at the rate of `15 W`, when its temperature is `227^(@)C`. Compare the area of the surface of the two bodies, if the surrounding is at `NTP`

A

`16:1`

B

`1:4`

C

`12:1`

D

`1:12`

Text Solution

Verified by Experts

The correct Answer is:
D
`P_(1)/(P_(2))= (sigmaA_(1)T_(1)^(4))/(sigmaA_(2)T_(2)^(4))`
or `(A_(1))/(A_(2))=(P_(1)T_(2)^(4))/(P_(2)T_(1)^(4))= (20)/(15)xx((227+273))/((272+273))=1/2`
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