NEET2016PhysicsThermal Properties of MatterActual

The temperature of a body is increased from -73^ C to 327^ C . Then the ratio of emissive power is

Options

A1 / 9
B1 / 27
C27
D81

Correct answer

D. 81

Step-by-step solution

Radiation from a body =RR=e T^4 time area, where e= emissive power e T^4= constant or e= ( constant T^4 ) or e₁ e₂ = ( T₂ T₁ )^4 or e₁ e₂ = ( 273+327 273-73 )^4= ( 600 200 )^4= (3)^4 1 = 81 1 or e₁ e₂ = 81 1

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