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The monochromatic emissivity € of a diffuse surface at 1600 K varies with wavelength in the following manner € = 0.4 for 0 < λ < 2 = 0.8 for 2 < λ < 5 Determine the total emissivity

The monochromatic emissivity € of a diffuse surface at 1600 K varies with wavelength in the following manner € = 0.4 for 0 < λ < 2 = 0.8 for 2 < λ < 5 Determine the total emissivity Correct Answer 0.5578

Total emissivity = 0.4 (-0.3181 – 0.0000) + 0.8 (0.8563 – 0.3118) = 0.5578.

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