1. A Carnot refrigeration cycle operates in a room in which the temperature is 20 °C. It is required to transfer heat from the cold space at the rate of 5 kW in order to maintain its temperature at -30 °C. What power motor is required to operate this refrigerator. 2. Calculate the thermal efficiency of a Carnot cycle heat engine operating between 500 °C and 40 °C.

1. A Carnot refrigeration cycle operates in a room in which the temperature is 20 °C. It is required to transfer heat from the cold space at the rate of 5 kW in order to maintain its temperature at -30 °C. What power motor is required to operate this refrigerator. 2. Calculate the thermal efficiency of a Carnot cycle heat engine operating between 500 °C and 40 °C.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 2RQ: The operating condition for the single compressor in a household refrigerator is the lowest box...

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