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KVPY2011PhysicsThermal Properties of Matter

The total radiative power emitted by spherical blackbody with radius R and temperature T is P . If the radius if doubled and the temperature is halved then the radiative power will be -

Options

AP / 4
BP / 2
C2 P
D4 P

Correct answer

A. P / 4

Step-by-step solution

P= A T⁴= 4 R² T⁴P^ = 4 (2 R)² ( T 2 )⁴P^ = 4 R² T⁴ 4 1 16 P^ = P 4

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