Two bodies A and B have thermal emissivities of 0.01 and 0.81. The outer surface areas of the two bodies are the same. The two bodies emit total radiant power at the same rate. The wavelength λ B co

Question

Two bodies A and B have thermal emissivities of 0.01 and 0.81. The outer surface areas of the two bodies are the same. The two bodies emit total radiant power at the same rate. The wavelength λ B ​ corresponding to maximum spectral radiance in the radiation from B is shifted from the wavelength corresponding to maximum spectral radiance from A by 1.00 μ m. If the temperature of A is 5802 K, then:

TestHub · Accepted Answer

Equal power and area give ϵ A ​ T A 4 ​ = ϵ B ​ T B 4 ​ , so T B ​ = 5802 ( 0.81 0.01 ​ ) to the power one quarter, which is 5802/3 = 1934 K. Wien: λ A ​ T A ​ = λ B ​ T B ​ , so λ B ​ = 3 λ A ​ . With λ B ​ − λ A ​ = 1.00 μ m, λ A ​ = 0.5 μ m and λ B ​ = 1.5 μ m. Options A and B.

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Options:(select one or more)

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