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A red star and a green star radiate ener...

A red star and a green star radiate energy at the same rate which star is bigger.

A

Red

B

Green

C

Both have same size

D

can't be say anything

Text Solution

Verified by Experts

The correct Answer is:
D
`(Q)/(t) = sigmaAT^(4)` = same but `T_("red") lt T_("green")`
as `lambda_("red") T_("red") = lambda_("green") T_("green")` (see `VIBGYOR`)
`implies` Area of red star is greater
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ALLEN -GEOMETRICAL OPTICS-EXERCISE -01
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