A- A grown man holds two metal balls with 5kg of mass in his both hands in one level. He started climbing a stair. Assuming a 20% mechanical efficiency in climbing stairs. In the middle of the stairs there is a fan that blows air with temperature of 25 °C, if the man body temperature is 39 °C, due to action he does. The sweat helped to keep his temperature at constant level. How much does the internal energy decrease when the man mass 65 kg and climbs a 15 m high of stairs? How much thermal energy does the person transfer to the environment as exhaust heat? What does the work the man does if he is climbing in speed of 2 m/s?. Assume the man volume is 0.25 m³.

A- A grown man holds two metal balls with 5kg of mass in his both hands in one level. He started climbing a stair. Assuming a 20% mechanical efficiency in climbing stairs. In the middle of the stairs there is a fan that blows air with temperature of 25 °C, if the man body temperature is 39 °C, due to action he does. The sweat helped to keep his temperature at constant level. How much does the internal energy decrease when the man mass 65 kg and climbs a 15 m high of stairs? How much thermal energy does the person transfer to the environment as exhaust heat? What does the work the man does if he is climbing in speed of 2 m/s?. Assume the man volume is 0.25 m³.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.39P: The tip of a soldering iron consists of a 0.6-cm- diameter copper rod, 7.6 cm long. If the tip must...

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