The emission spectrum of a blackbody is shown at two temperatures: T1 = 27 deg C and T2 = 327 deg C. Let A1 and A2 be the areas under the two spectral curves respectively. What is the value of A2/A1?

1: 16
4: 1
2: 1
16: 1

Correct answer: 16: 1

Solution

By Stefan-Boltzmann law, the total energy radiated (area under the blackbody curve) is proportional to T⁴. T1 = 300 K, T2 = 600 K. A2/A1 = (600/300)⁴ = 2⁴ = 16.

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