An ideal refrigerator or ideal heat pump is equivalent to a Carnot engine running in reverse. That is, energy |Qc| is taken in from a cold reservoir and energy |Qh| is rejected to a hot reservoir. (a) Show that the work that must he supplied to run the refrigerator or heat pump is
(b) Show that the coefficient of performance (COP) of the ideal refrigerator is
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Chapter 21 Solutions
Physics for Scientists and Engineers
- Show that the coefficients of performance of refrigerators and heat pumps are related by COPref=COPhp1. Start with the definitions of the COP s and the conservation of energy relationship between Qh, QC, and W.arrow_forwardA copper rod of cross-sectional area 5.0 cm2 and length 5.0 m conducts heat from a heat reservoir at 373 K to one at 273 K. What is the time rate of change of the universe's entropy for this process?arrow_forwardWhich of the following is true for the entropy change of a system that undergoes a reversible, adiabatic process? (a) S 0 (b) S = 0 (c) S 0arrow_forward
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