The total e-missive power of a surface is 500 W/ m2 at temperature

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The total e-missive power of a surface is 500 W/ m² at temperature T₁ and 1200 W/m² at temperature T₂, where the temperature are in Kelvin. Assuming the e-missivity of the surface to be constant, the ratio of the temperature T₁ /T₂ is

1. 0.0308
2. 0.416
3. 0.803
4. 0.874

Correct Option: C

E-missive power ∝ T⁴

⇒	500	=		T₁		⁴
	1200			T₂

∴	T₁	= 0.8034
	T₂