(4 blanks) An ice-making machine operates in a Carnot cycle. It takes heat from water at 0.0 °C and rejects heat to a room at 24.0 °C. Suppose that 85.0 kg of water at 0.0 °C are converted to ice at 0.0 °C. How much energy (in Joules) must be supplied to the machine to achieve this task? Sol. Since the machine is a operating in a Carnot cycle, then, its efficiency is ITHỊ By virtue of first law, the work done to convert water to ice is given by W = Q = Thus, the total energy needed to convert 85 kg of water is ET = 687.5 J

(4 blanks) An ice-making machine operates in a Carnot cycle. It takes heat from water at 0.0 °C and rejects heat to a room at 24.0 °C. Suppose that 85.0 kg of water at 0.0 °C are converted to ice at 0.0 °C. How much energy (in Joules) must be supplied to the machine to achieve this task? Sol. Since the machine is a operating in a Carnot cycle, then, its efficiency is ITHỊ By virtue of first law, the work done to convert water to ice is given by W = Q = Thus, the total energy needed to convert 85 kg of water is ET = 687.5 J

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter22: Heat Engines, Entropy, And The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 22.4OQ: Of the following, which is not a statement of the second law of thermodynamics? (a) No heat engine...

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