In exercising, a weight lifter loses 0.177 kg of water through evaporation, the heat required to evaporate the water coming from the weight lifter's body. The work done in lifting weights is 1.78 x 10^5J. (a) Assuming that the latent heat of vaporization of perspiration is 2.42 x 10^6J/kg, find the chnage in the internal energy of the weight lifter. (b) Determine the minimum number of nutrtional calories of food that must be consumed to replace the loss of internal energy. (1 nutritonal Calorie= 4186 J)

In exercising, a weight lifter loses 0.177 kg of water through evaporation, the heat required to evaporate the water coming from the weight lifter's body. The work done in lifting weights is 1.78 x 10^5J. (a) Assuming that the latent heat of vaporization of perspiration is 2.42 x 10^6J/kg, find the chnage in the internal energy of the weight lifter. (b) Determine the minimum number of nutrtional calories of food that must be consumed to replace the loss of internal energy. (1 nutritonal Calorie= 4186 J)

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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