College Physics
2nd Edition
ISBN: 9780134601823
Author: ETKINA, Eugenia, Planinšič, G. (gorazd), Van Heuvelen, Alan
Publisher: Pearson,
expand_more
expand_more
format_list_bulleted
Videos
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.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
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...
Additional Science Textbook Solutions
Find more solutions based on key concepts
The speed of the person sitting on the chair relative to the chair and relative to Earth.
Conceptual Physics (12th Edition)
3. What is free-fall, and why does it make you weightless? Briefly describe why astronauts are weightless in th...
The Cosmic Perspective (8th Edition)
A ball rebounds elastically from the floor. What doesthis situation share with the ideas of momentum conservati...
Modern Physics
How do headlands form?
Conceptual Integrated Science
3. What is free-fall, and why does it make you weightless? Briefly describe why astronauts are weightless in th...
The Cosmic Perspective
Q19.11 When you blow on the back of your hand with your mouth wide open, your breath feels warm. But if you pa...
University Physics with Modern Physics (14th Edition)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- A heat pump has a coefficient of performance equal to 4.20 and requires a power of 1.75 kW to operate. (a) How much energy does the heat pump add to a home in one hour? (b) If the heat pump is reversed so that it acts as an air conditioner in the summer, what would be its coefficient of performance?arrow_forwardA power plant has been proposed that would make use of the temperature gradient in the ocean. The system is to operate between 20.0C (surface water temperature) and 5.00C (water temperature at a depth of about 1 km). (a) What is the maximum efficiency of such a system? (b) If the useful power output of the plant is 75.0 MW, how much energy is absorbed per hour? (c) In view of your answer to part (a), do you think such a system is worthwhile (considering that there is no charge for fuel)?arrow_forwardA thermal engine produces 4 MJ of electrical energy while operating between two thermal baths of different temperatures. The working substance of the engine discharges 5 MJ of heat to the cold temperature bath. What is the efficiency of the engine?arrow_forward
- (a) What is the best coefficient of performance for a refrigerator that cools an environment at 30.0C and has heat transfer to another environment at 45.0C ? (b) How much work in joules must be done for a heat transfer of 4186 kJ from the cold environment? (c) What is the cost of doing this if the work costs 10.0 cents per 3.60106J (a kilowatthour)? (d) How many kJ of heat transfer occurs into the warm environment? (e) Discuss what type of refrigerator might operate between these temperatures.arrow_forwardSuppose an ideal (Carnot) heat pump could be constructed for use as an air conditioner. (a) Obtain an expression for the coefficient of performance (COP) for such an air conditioner in terms of Tb and Tc. (b) Would such an air conditioner operate on a smaller energy input if the difference in the operating temperatures were greater or smaller? (c) Compute the COP for such an air conditioner if the indoor temperature is 20.0C and the outdoor temperature is 40.0C.arrow_forward(a) How long will the energy in a 1470kJ (350kcal) cup of yogurt last in a woman doing work at the rate of 150 W with an efficiency of 20.0% (such as in leisurely climbing stairs)? (b) Does the time found in part (a) imply that it is easy to consume more food energy than you can reasonably expect to work off with exercise?arrow_forward
- A large electrical power station generates 1000 MW of electricity with an efficiency of 35.0%. (a) Calculate the heat transfer to the power station, Qh, in one day. (b) How much heat transfer Qc occurs to the environment in one day? (c) If the heat transfer in the cooling towers is from 35.0C water into the local air mass, which increases in temperature from 18.0C to 20.0C, what is the total increase in entropy due to this heat transfer? (d) How much energy becomes unavailable to do work because of this increase in entropy, assuming an 18.0C lowest temperature? (Part of Qccould be utilized to operate heat engines or far simply heating the surroundings, but it rarely is.)arrow_forwardAn engine with an efficiency of 0.36 can supply a power of 140 hp. At what rate does it exhaust heat to the environment? Express your answer in watts.arrow_forward(a) In reaching equilibrium, how much heat transfer occurs from 1.00 kg of water at 40.0C when it is placed in contact with 1.00 kg of 20.0C water in reaching equilibrium? (b) What is the change in entropy due to this heat transfer? (c) How much work is made unavailable, taking the lowest temperature to be 20.0C ? Explicitly show how you follow the steps in the Problem-Solving Strategies for Entropy.arrow_forward
- (a) What is the best coefficient of performance for a heat pump that has a hot reservoir temperature of 50.0C and a cold reservoir temperature of 20.0C ? (b) How much heat transfer occurs into the warm environment if 3.60107J of work (10.0kWh) is put into it? (c) If the cost of this work input is 10.0cent/kWh, haw does its cost compare with the direct heat transfer achieved by burning natural gas at a cost of 85.0 cents per therm. (A therm is a common unit of energy for natural gas and equals 1.055108J .)arrow_forward(a) Ten grams of H2O stats as ice at 0 . The ice absorbs heat from the air (just above 0 ) until all of it melts. Calculate the entropy change of the H2O, of the air, and of the universe. (b) Suppose that the air in part (a) is at 20 rather than 0 and that the ice absorbs heat until it becomes water at 20 . Calculate the entropy change of the H2O, of the air, and of the universe. (c) Is either of these processes reversible?arrow_forward(a) What is the hot reservoir temperature of a Carnot engine that has an eficiency of 42.0% and a cold reservoir temperature of 210C ? (b) What must the hot reservoir temperature be for a real heat engine that achieves 0.700 of the maximum eficiency, but still has an efficiency of 42.0% (and a cold reservoir at 27.0C )? (c) Does your answer imply practical limits to the efficiency of car gasoline engines?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Physics for Scientists and EngineersPhysicsISBN:9781337553278Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Physics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
College PhysicsPhysicsISBN:9781938168000Author:Paul Peter Urone, Roger HinrichsPublisher:OpenStax College
Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Physics for Scientists and Engineers
Physics
ISBN:9781337553278
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781938168000
Author:Paul Peter Urone, Roger Hinrichs
Publisher:OpenStax College
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
The Second Law of Thermodynamics: Heat Flow, Entropy, and Microstates; Author: Professor Dave Explains;https://www.youtube.com/watch?v=MrwW4w2nAMc;License: Standard YouTube License, CC-BY