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 190 cm2 and its emissivity is 0.84. (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 0.56?

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 190 cm2 and its emissivity is 0.84. (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 0.56?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 71PQ

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