College Physics
2nd Edition
ISBN: 9780134601823
Author: ETKINA, Eugenia, Planinšič, G. (gorazd), Van Heuvelen, Alan
Publisher: Pearson,
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Textbook Question
Chapter 16, Problem 38GP
* A refrigerator transfers 700 J of thermal energy every second to a room while 580 J of thermal energy is transferred every second from its cool reservoir. The inside of the refrigerator is
Determine (a) the performance coefficient of the refrigerator and (b) the power of the refrigerator engine.
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PROBLEM 4
A heat pump is used to meet the heating requirements of a house and maintain it at a
comfortable temperature. On an average winter day, the house is estimated to lose heat at a
rate of 80,000 kJ h¯¹. The heat pump has a COP of 2.5 under these conditions.
Questions:
(a) Determine the net power input required by the heat pump, in kW.
(b) The rate at which heat is extracted from the cold outdoor air, in kW.
A NATO base in northern Norway is warmed with a heat pump that uses 7.0°C ocean water
as the cold reservoir. Heat extracted from the ocean water warms fluid to 80°C; this warmed
fluid is used to heat the building. When the system is working at full capacity, 2000 kW of
heat are delivered to the
building at the cost of 600 kW of electrie energy.
a. What is the actual coefficient of performance of the system?
b. What is the theoretical maximum coefficient of performance of the system?
а.
What is the coefficient of performance of a refrigerator? Let Q1 be the heat released to hot reservoir, Q2 be the heat extracted from a cold reservoir & W be the work done on the refrigerator.
a) Q1/W
b) Q1/Q2
c) Q2/W
d) Q2/Q1
Chapter 16 Solutions
College Physics
Ch. 16 - Prob. 1RQCh. 16 - Prob. 2RQCh. 16 - Prob. 3RQCh. 16 - Prob. 4RQCh. 16 - Which of the following processes is reversible?...Ch. 16 - In physics the collision of billiard balls is...Ch. 16 - Prob. 3MCQCh. 16 - 4. When driving a car (the system), what object...Ch. 16 - 5. The law of energy conservation says that energy...Ch. 16 - Prob. 6MCQ
Ch. 16 - Entropy can be calculated using which of the...Ch. 16 - Prob. 8MCQCh. 16 - 9. When a drop of ink enters a glass of water and...Ch. 16 - 10. Choose the best reason why the following...Ch. 16 - Prob. 11MCQCh. 16 - Which of the following changes will always...Ch. 16 - Entropy change is easier to determine for...Ch. 16 - 14. Describe five everyday examples of processes...Ch. 16 - Prob. 15CQCh. 16 - 16. In terms of the statistical definition of...Ch. 16 - 17. The entropy of the molecules that form leaves...Ch. 16 - Prob. 18CQCh. 16 - Below, BIO indicates a problem with a biological...Ch. 16 - Below, BIO indicates a problem with a biological...Ch. 16 - Prob. 3PCh. 16 - Below, BIO indicates a problem with a biological...Ch. 16 - Prob. 5PCh. 16 - 6. (a) Identify all of the macrostate...Ch. 16 - 7. * Repeat the previous problem for a system with...Ch. 16 - * Determine the ratio of the number of microstates...Ch. 16 - Prob. 9PCh. 16 - 10. * Parachutists landing on island Parachutists...Ch. 16 - Prob. 11PCh. 16 - * Nine numbered balls are dropped randomly into...Ch. 16 - * Rolling dice Two dice are rolled Macrostates of...Ch. 16 - 14.* (a) Apply your knowledge of probability to...Ch. 16 - Explain using your knowledge of probability why a...Ch. 16 - * EST Estimate the total change in entropy of two...Ch. 16 - 17. * EST (a) You add 0.1 kg of water at of iced...Ch. 16 - * Entropy change of a house A house at 20C...Ch. 16 - 19. ** Barrel of water in cellar in winter A...Ch. 16 - 20. * EST (a) Determine the final temperature when...Ch. 16 - * A 5.0-kg block slides on a level surface and...Ch. 16 - with the horizontal. Determine the entropy change...Ch. 16 - Prob. 23PCh. 16 - * BIO Efficiency of woman walking A 60-kg woman...Ch. 16 - Prob. 25PCh. 16 - 26. ** A cyclic process involving 1 mole of ideal...Ch. 16 - 27. ** A cyclic process involving 1 mole of ideal...Ch. 16 - Prob. 28PCh. 16 - Prob. 29PCh. 16 - Prob. 30PCh. 16 - Prob. 31PCh. 16 - 32. Rank the engines that operate with the...Ch. 16 - 33. Nuclear power plant A nuclear power plant...Ch. 16 - Prob. 34PCh. 16 - Prob. 35GPCh. 16 - W=AUint. W=(3.0)105N/m2 )(0.020m30.010m3)+0...Ch. 16 - * A thermodynamic engine operates between two...Ch. 16 - 38. * A refrigerator transfers 700 J of thermal...Ch. 16 - Prob. 39RPPCh. 16 - Prob. 40RPPCh. 16 - Fuel used to counter air resistance The resistive...Ch. 16 - Prob. 42RPPCh. 16 - Prob. 43RPPCh. 16 - The value of CA for a Ford Escape Hybrid is...
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