Physics for Scientists and Engineers, Technology Update (No access codes included)
9th Edition
ISBN: 9781305116399
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 22, Problem 22.66AP
Suppose 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 20.0°C and the outdoor temperature is 40.0°C.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A heat pump has a coefficient of performance of 3.75 and operates with a power consumption of 715 W.
(a) How much energy does it deliver into a home during 2 h of continuous operation?
(b) How much energy does it extract from the outside air in 2 h?
Need Help?
Read It
A refrigerator is characterized by a number called the coefficient of performance (COP), which is defined as the heat removed from the cool place (inside the fridge) divided by the work required to
remove that heat:
COP = Q/w.
(a) If you are buying a new fridge is it better to buy one with a higher COP or a lower COP?
O higher
O lower
O it doesn't matter
Let's say that a fridge operates between temperatures of 4°C and 31.0°C. A particular fridge has a COP of 4.50.
(b) If 500 of work is done by the compressor in the fridge to extract heat from inside the fridge, how much heat is removed from inside the fridge?
(c) How much heat is dumped by the fridge into the surroundings, in this case?
(d) What is the maximum possible COP that would be achieved by an ideal fridge operating between the two temperatures specified above?
A heat engine is being designed to have a Carnot efficiency of 60% when operating between two heat reservoirs.
(a) If the temperature of the cold reservoir is 20°C, what must be the temperature of the hot reservoir?
°C
(b) Can the actual efficiency of the engine be equal to 60%?
O Yes
O No
Explain your answer.
Chapter 22 Solutions
Physics for Scientists and Engineers, Technology Update (No access codes included)
Ch. 22 - The energy input to an engine is 4.00 times...Ch. 22 - The energy entering an electric heater by...Ch. 22 - Three engines operate between reservoirs separated...Ch. 22 - (a) Suppose you select four cards at random from a...Ch. 22 - An ideal gas is taken from an initial temperature...Ch. 22 - True or False: The entropy change in an adiabatic...Ch. 22 - The second law of thermodynamics implies that the...Ch. 22 - Assume a sample of an ideal gas is at room...Ch. 22 - A refrigerator has 18.0 kJ of work clone on it...Ch. 22 - Of the following, which is not a statement of the...
Ch. 22 - Consider cyclic processes completely characterized...Ch. 22 - Prob. 22.6OQCh. 22 - A steam turbine operates at a boiler temperature...Ch. 22 - A thermodynamic process occurs in which the...Ch. 22 - A sample of a monatomic ideal gas is contained in...Ch. 22 - An engine does 15.0 kJ of work while exhausting...Ch. 22 - The arrow OA in the PV diagram shown in Figure...Ch. 22 - The energy exhaust from a certain coal-fired...Ch. 22 - Discuss three different common examples of natural...Ch. 22 - Prob. 22.3CQCh. 22 - The first law of thermodynamics says you cant...Ch. 22 - Energy is the mistress of the Universe, and...Ch. 22 - Prob. 22.6CQCh. 22 - The device shown in Figure CQ22.7, called a...Ch. 22 - A steam-driven turbine is one major component of...Ch. 22 - Discuss the change in entropy of a gas that...Ch. 22 - Prob. 22.10CQCh. 22 - Prob. 22.11CQCh. 22 - (a) If you shake a jar full of jelly beans of...Ch. 22 - Prob. 22.13CQCh. 22 - A particular heat engine has a mechanical power...Ch. 22 - The work done by an engine equals one-fourth the...Ch. 22 - A heat engine takes in 360 J of energy from a hot...Ch. 22 - A gun is a heat engine. In particular, it is an...Ch. 22 - An engine absorbs 1.70 kJ from a hot reservoir at...Ch. 22 - A multicylinder gasoline engine in an airplane,...Ch. 22 - Suppose a heat engine is connected to two energy...Ch. 22 - A refrigerator has a coefficient of performance...Ch. 22 - During each cycle, a refrigerator ejects 625 kJ of...Ch. 22 - A heat pump has a coefficient of performance of...Ch. 22 - A refrigerator has a coefficient of performance of...Ch. 22 - A heat pump has a coefficient of performance equal...Ch. 22 - A freezer has a coefficient of performance of...Ch. 22 - Prob. 22.14PCh. 22 - One of the most efficient heat engines ever built...Ch. 22 - Why is the following situation impossible? An...Ch. 22 - A Carnot engine has a power output of 150 kW. The...Ch. 22 - A Carnot engine has a power output P. The engine...Ch. 22 - What is the coefficient of performance of a...Ch. 22 - An ideal refrigerator or ideal heat pump is...Ch. 22 - Prob. 22.21PCh. 22 - How much work does an ideal Carnot refrigerator...Ch. 22 - If a 35.0% -efficient Carnot heat engine (Fig....Ch. 22 - A power plant operates at a 32.0% efficiency...Ch. 22 - A heat engine is being designed to have a Carnot...Ch. 22 - A Carnot heat engine operates between temperatures...Ch. 22 - An ideal gas is taken through a Carnot cycle. The...Ch. 22 - Prob. 22.28PCh. 22 - Prob. 22.29PCh. 22 - Suppose you build a two-engine device with the...Ch. 22 - Argon enters a turbine at a rate of 80.0 kg/min, a...Ch. 22 - At point A in a Carnot cycle, 2.34 mol of a...Ch. 22 - An electric generating station is designed to have...Ch. 22 - An ideal (Carnot) freezer in a kitchen has a...Ch. 22 - A heat pump used for heating shown in Figure...Ch. 22 - A gasoline engine has a compression ratio of 6.00....Ch. 22 - In a cylinder of an automobile engine, immediately...Ch. 22 - An idealized diesel engine operates in a cycle...Ch. 22 - Prob. 22.39PCh. 22 - (a) Prepare a table like Table 21.1 for the...Ch. 22 - Prob. 22.41PCh. 22 - An ice tray contains 500 g of liquid water at 0C....Ch. 22 - A Styrofoam cup holding 125 g of hot water at 100C...Ch. 22 - A 1.00-kg iron horseshoe is taken from a forge at...Ch. 22 - A 1 500-kg car is moving at 20.0 m/s. The driver...Ch. 22 - Prob. 22.46PCh. 22 - Prob. 22.47PCh. 22 - 1.00-mol sample of H2 gas is contained in the left...Ch. 22 - A 2.00-L container has a center partition that...Ch. 22 - What change in entropy occurs when a 27.9-g ice...Ch. 22 - Calculate the change in entropy of 250 g of water...Ch. 22 - How fast are you personally making the entropy of...Ch. 22 - When an aluminum bar is connected between a hot...Ch. 22 - When a metal bar is connected between a hot...Ch. 22 - Prob. 22.55PCh. 22 - Calculate the increase in entropy of the Universe...Ch. 22 - How much work is required, using an ideal Carnot...Ch. 22 - Prob. 22.58APCh. 22 - The energy absorbed by an engine is three times...Ch. 22 - Prob. 22.60APCh. 22 - Prob. 22.61APCh. 22 - In 1993, the U.S. government instituted a...Ch. 22 - Prob. 22.63APCh. 22 - One mole of neon gas is heated from 300 K to 420 K...Ch. 22 - Au airtight freezer holds n moles of air at 25.0C...Ch. 22 - Suppose an ideal (Carnot) heat pump could be...Ch. 22 - In 1816, Robert Stirling, a Scottish clergyman,...Ch. 22 - A firebox is at 750 K, and the ambient temperature...Ch. 22 - Review. This problem complements Problem 44 in...Ch. 22 - A biology laboratory is maintained at a constant...Ch. 22 - A power plant, having a Carnot efficiency,...Ch. 22 - A power plant, having a Carnot efficiency,...Ch. 22 - A 1.00-mol sample of an ideal monatomic gas is...Ch. 22 - A system consisting of n moles of an ideal gas...Ch. 22 - A heat engine operates between two reservoirs at...Ch. 22 - A 1.00-mol sample of a monatomic ideal gas is...Ch. 22 - A sample consisting of n moles of an ideal gas...Ch. 22 - An athlete whose mass is 70.0 kg drinks 16.0...Ch. 22 - Prob. 22.79APCh. 22 - Prob. 22.80APCh. 22 - A 1.00-mol sample of an ideal gas ( = 1.40) is...Ch. 22 - The compression ratio of an Otto cycle as shown in...
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
- 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_forwardFind the work done in the quasi-static processes shown below. The states are given as (p, V) values for the points in the PV plane: 1 (3 atm, 4 L), 2 (3 atm, 6 L), 3 (5 atm, 4 L), 4 (2 atm, 6 L), 5 (4 atm, 2 L), 6 (5 atm, 5 L) and 7 (2 atm, 5 L).arrow_forward
- Of the following, which is not a statement of the second law of thermodynamics? (a) No heat engine operating in a cycle can absorb energy from a reservoir and use it entirely to do work, (b) No real engine operating between two energy reservoirs can be more efficient than a Carnot engine operating between the same two reservoirs, (c) When a system undergoes a change in state, the change in the internal energy of the system is the sum of the energy transferred to the system by heat and the work done on the system, (d) The entropy of the Universe increases in all natural processes, (e) Energy will not spontaneously transfer by heat from a cold object to a hot object.arrow_forwardTrue or False: The entropy change in an adiabatic process must be zero because Q = 0.arrow_forwardUse a PV diagram such as the one in Figure 22.2 (page 653) to figure out how you could modify an engine to increase the work done.arrow_forward
- A heat pump used to warm a home must employ a cycle that produces a working fluid at temperatures greater than typical indoor temperature so that heat transfer to the inside can take place. Similarly, it must produce a working fluid at temperatures that are colder than the outdoor temperature so that heat transfer occurs from outside. Its hot and cold reservoir temperatures therefore cannot be too close, placing a limit on its COPhp . What is the best coefficient of performance possible for such a heat pump, if it has a hot reservoir temperature of 45.0ºC and a cold reservoir temperature of −15.0ºC ?arrow_forwardYou are working on a summer job at a company that designs non-traditional energy systems. The company is working on a proposed electric power plant that would make use of the temperature gradient in the ocean. The system includes a heat engine that would operate between 20.0°C (surfacewater temperature) and 5.00°C (water temperature at a depth of about 1 km). (a) Your supervisor asks you to determine the maximum efficiency of such a system. (b) In addition, if the electric power output of the plant is 75.0 MW and it operates at the maximum theoretically possible efficiency, you must determine the rate at which energy is taken in from the warm reservoir. (c) From this information, if an electric bill for a typical home shows a use of 950 kWh per month, your supervisor wants to know how many homes can be provided with power from this energy system operating at its maximum efficiency. (d) As energy is drawn from the warm surface water to operate the engine, it is replaced by energy…arrow_forwardSuppose you want to operate an ideal refrigerator that has a cold temperature of -7.5°C, and you would like it to have a coefficient of performance of 6.5. What is the temperature, in degrees Celsius, of the hot reservoir for such a refrigerator?arrow_forward
- What is the best coefficient of performance possible for such a heat pump, if it has a hot reservoir temperature of 45.0°C and a cold reservoir temperature of -15.0°C?arrow_forwardA certain Carnot engine was built in a laboratory. The lab technicians found out that if the temperature of the cold reservoir is kept at 295 K, the efficiency of the engine is 26.0%. If the hot reservoir is kept at constant temperature, at what temperature must the cold reservoir be set, so that the efficiency of the engine is increased to 33.0%?arrow_forwardA heat engine is designed to do work. This is possible only if certain relationships between the heats and temperatures at the input and output hold true. Which of the following sets of statements must apply for the heat engine to do work? Find the work W done by the "ideal" heat engine. Find The thermal efficiency eee of a heat engine is defined as follows: e=W/Qharrow_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 Engineers, Technology ...PhysicsISBN:9781305116399Author: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, Technology ...
Physics
ISBN:9781305116399
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