EBK PHYSICS FOR SCIENTISTS AND ENGINEER
6th Edition
ISBN: 9781319321710
Author: Mosca
Publisher: VST
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Question
Chapter 19, Problem 49P
(a)
To determine
The maximum possible COP for a heat pump.
(b)
To determine
The minimum power of the electric motor.
(c)
To determine
The minimum power of the electric motor when the COP is 60 percent of the ideal value.
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Students have asked these similar questions
(a) What is the best coefficient of performance for a heat pump that has a hot reservoir temperature of 53.3°C and a cold reservoir temperature of -12.2°C?
4.982
(b) How much heat in kilocalories would it pump into the warm environment if 3.60 x 107 ) of work (10.0 kw · h) is put into it?
4.287e4
v kcal
(c) Assume the cost of this work input is 10c/kW · h. Also assume that the cost of direct production of heat by burning natural gas is 81.0c per therm (a common unit of energy for natural gas), where a therm
equals 1.055 x 10° J. Compare the cost of producing the same amount of heat by each method.
cost of heat pump
= 0,692
cost of natural gas
Check unit conversions and your calculations.
A certain brand of freezer is advertised to use 730 kW . hof energy per year. (a) Assuming the freezer operates for 5 hours eachday, how much power does it require while operating? (b) If the freezerkeeps its interior at -5.0 C in a 20.0 C room, what is its theoreticalmaximum performance coefficient? (c) What is the theoretical maximumamount of ice this freezer could make in an hour, starting withwater at 20.0 C?
How much heat QH does a heat pump with a coefficient of performance of 2.00 deliver when supplied with 4.10 kJ
of electricity?
Он
J
Chapter 19 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
Ch. 19 - Prob. 1PCh. 19 - Prob. 2PCh. 19 - Prob. 3PCh. 19 - Prob. 4PCh. 19 - Prob. 5PCh. 19 - Prob. 6PCh. 19 - Prob. 7PCh. 19 - Prob. 8PCh. 19 - Prob. 9PCh. 19 - Prob. 10P
Ch. 19 - Prob. 11PCh. 19 - Prob. 12PCh. 19 - Prob. 13PCh. 19 - Prob. 14PCh. 19 - Prob. 15PCh. 19 - Prob. 16PCh. 19 - Prob. 17PCh. 19 - Prob. 18PCh. 19 - Prob. 19PCh. 19 - Prob. 20PCh. 19 - Prob. 21PCh. 19 - Prob. 22PCh. 19 - Prob. 23PCh. 19 - Prob. 24PCh. 19 - Prob. 25PCh. 19 - Prob. 26PCh. 19 - Prob. 27PCh. 19 - Prob. 28PCh. 19 - Prob. 29PCh. 19 - Prob. 30PCh. 19 - Prob. 31PCh. 19 - Prob. 32PCh. 19 - Prob. 33PCh. 19 - Prob. 34PCh. 19 - Prob. 35PCh. 19 - Prob. 36PCh. 19 - Prob. 37PCh. 19 - Prob. 38PCh. 19 - Prob. 39PCh. 19 - Prob. 40PCh. 19 - Prob. 41PCh. 19 - Prob. 42PCh. 19 - Prob. 43PCh. 19 - Prob. 44PCh. 19 - Prob. 45PCh. 19 - Prob. 46PCh. 19 - Prob. 47PCh. 19 - Prob. 48PCh. 19 - Prob. 49PCh. 19 - Prob. 50PCh. 19 - Prob. 51PCh. 19 - Prob. 52PCh. 19 - Prob. 53PCh. 19 - Prob. 54PCh. 19 - Prob. 55PCh. 19 - Prob. 56PCh. 19 - Prob. 57PCh. 19 - Prob. 58PCh. 19 - Prob. 59PCh. 19 - Prob. 60PCh. 19 - Prob. 61PCh. 19 - Prob. 62PCh. 19 - Prob. 63PCh. 19 - Prob. 64PCh. 19 - Prob. 65PCh. 19 - Prob. 66PCh. 19 - Prob. 67PCh. 19 - Prob. 68PCh. 19 - Prob. 69PCh. 19 - Prob. 70PCh. 19 - Prob. 71PCh. 19 - Prob. 72PCh. 19 - Prob. 73PCh. 19 - Prob. 74PCh. 19 - Prob. 75PCh. 19 - Prob. 76PCh. 19 - Prob. 77PCh. 19 - Prob. 78PCh. 19 - Prob. 79PCh. 19 - Prob. 80PCh. 19 - Prob. 81PCh. 19 - Prob. 82PCh. 19 - Prob. 83PCh. 19 - Prob. 84PCh. 19 - Prob. 85PCh. 19 - Prob. 86PCh. 19 - Prob. 87PCh. 19 - Prob. 88PCh. 19 - Prob. 89P
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