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A star behaves like perfeact Black body ...

A star behaves like perfeact Black body emitting radiant energy The ratio of radiant energy emitted per sec by this star to that emitted by an another star having having `8times the radius of the former but having Kelvin temperature one fourth of the former is .

A

`1:4`

B

`1:8`

C

`4:1`

D

`1:16`

Text Solution

Verified by Experts

The correct Answer is:
C
`P = sigma AT^(4) rArr P = sigma 4 pi R^(2) T^(4)`
`:. (P_(2))/(P_(1))=((R_(2))/(R_(1)))^(2)((T_(2))/(T_(1)))^(4)` .
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