(a) What is the best coefficient of performance for a refrigerator that cools an environment at -28 C and has heat transfer to another environment at 49 ° C? COP, = 3.18 ref (b) How much work must be done for a heat transfer of 4186 kJ from the cold environment? W = 1316.4 kJ (c) What is the cost of doing this if the work costs 10.0 cents per 3.6x10° J (a kilowatt-hour)? Cost in cents = 3.66 (d) How many kJ of heat transfer, Q, occurs into the warm environment? Qn = 1314.5

(a) What is the best coefficient of performance for a refrigerator that cools an environment at -28 C and has heat transfer to another environment at 49 ° C? COP, = 3.18 ref (b) How much work must be done for a heat transfer of 4186 kJ from the cold environment? W = 1316.4 kJ (c) What is the cost of doing this if the work costs 10.0 cents per 3.6x10° J (a kilowatt-hour)? Cost in cents = 3.66 (d) How many kJ of heat transfer, Q, occurs into the warm environment? Qn = 1314.5

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter15: Thermodynamics

Section: Chapter Questions

Problem 46PE: Show that the coefficients of performance of refrigerators and heat pumps are related by...

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