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PhysicsQ&A LibraryA person is standing outdoors in the shade where the temperature is 21 °C. (a) What is the radiant energy absorbed per second by his head when it is covered with hair? The surface area of the hair (assumed to be flat) is 130 cm2 and its emissivity is 0.90. (b) What would be the radiant energy absorbed per second by the same person if he were bald and the emissivity of his head were 0.54?Start your trial now! First week only $4.99!*arrow_forward*

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A person is standing outdoors in the shade where the temperature is 21 °C. **(a)** What is the radiant energy absorbed per second by his head when it is covered with hair? The surface area of the hair (assumed to be flat) is 130 cm^{2} and its emissivity is 0.90. **(b)** What would be the radiant energy absorbed per second by the same person if he were bald and the emissivity of his head were 0.54?

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