A person is standing outdoors in the shade where the temperature is 20 °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 160 cm² and its emissivity is 0.81. (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 0.68?

A person is standing outdoors in the shade where the temperature is 20 °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 160 cm² and its emissivity is 0.81. (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 0.68?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 128CP: As the very first rudiment of climatology, estimate the temperature of Earth. Assume it is a perfect...

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