In exercising, a weight lifter loses 0.130 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 1.36E+5 J. Assuming that the latent heat of vaporization of perspiration is 2.44E+6 J/kg, find the change in the internal energy of the weight lifter.
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The weightlifter loses internal energy by 2 processes:
1. Direct work output
2. Heat loss by latent heat of water vapor
(direct conductive or convective loss is not considered here)
The total change in internal energy is -1.36e5J work - (0.130 kg * 2.44e6 J/kg) evaporative. You do the math.
1. Direct work output
2. Heat loss by latent heat of water vapor
(direct conductive or convective loss is not considered here)
The total change in internal energy is -1.36e5J work - (0.130 kg * 2.44e6 J/kg) evaporative. You do the math.