A black body at 227°C radiates heat at the rate of 7 cals/cm²s.

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A black body at 227°C radiates heat at the rate of 7 cals/cm²s. At a temperature of 727°C, the rate of heat radiated in the same units will be:

1. 50
2. 112
3. 80
4. 60

Correct Option: B

According to Stefan’s law E = σT⁴,
T₁ = 500 K
T₂ = 1000 K

E₂	=		T₂		⁴	=		1000		⁴	= 16
E₁			T₁					500

∴ E₂ = 16 × 7 = 112 cal / cm²s