A black body at 227⁰C radiates heat at the rate of 7cals/cm²s. At a temperature

A black body at 227⁰C radiates heat at the rate of 7cals/cm²s. At a temperature of 727⁰C, the rate of heat radiated in the same units will be:

Options

(a) 50
(b) 112
(c) 80
(d) 60

Correct Answer:

112

Explanation:

According to Stefan’s law, E ∞ σT⁴, T₁ = 500 K T₂ = 1000 K
E₂ / E₁ = (T₂ / T₁)⁴ = (1000 / 500)⁴ = 16
E₂ = 16 x 7 = 112 cal/ cm²s

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