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Two spherical bodies have radii R,2R and...

Two spherical bodies have radii `R,2R` and emissivities e,2e If the temperature ratio is `2:1` then the powers will be in the ratio .

A

`1 :1`

B

`2:1`

C

`3:1`

D

`4:1`

Text Solution

Verified by Experts

The correct Answer is:
B
`P = e sigma AT^(4) rArr P = e sigma 4 pi R^(20 T^(4)`
`:.(P_(1))/(P_(2))((T_(1))/(T_(2)))(e_(1))/(e_(2))xx(R_(1))/(R_(2))` .
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