The human eye is more sensitive to the yellow-green part of the visible spectrum because this is where the irradiance of the sun is maximum. Since the sun can be considered as a blackbody with a temperature of approximately 5800 K, use Planck’s relation for the irradiance of a blackbody to find the wavelength of the maximum of the sun irradiance. You will come out with a very simple relation between the peak of the irradiance (λ_peak) and T, which is called Wien’s relation. In Planck’s relation above, h, c, λ, kb, and T are, respectively, Planck’s constant, the velocity of light in vacuum, the wavelength, Boltzmann’s constant, and the absolute temperature. You will need the following solution for the equation x ¼ 5(1-e^-x), x ^¼ 4.965. Then use Wien’s relation to estimate λpeak for a human body.

Transcribed Image Text:

I(2) = 2ay 2nhc? hc