Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
4th Edition
ISBN: 9780133942651
Author: Randall D. Knight (Professor Emeritus)
Publisher: PEARSON
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Chapter 21, Problem 7EAP
The power output of a car engine running at 2400 rpm is 500 kW. How much (a) work is done and (b) heat is exhausted per cycle if the engine's thermal efficiency is 20%? Give your answers in kJ.
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The power output of a car engine running at 2300 rpmrpm is 300 kW .
(a) How much work is done per cycle if the engine's thermal efficiency is 40.0 %?Give your answer in kJ.
Win =7.83kJ
(b)How much heat is exhausted per cycle if the engine's thermal efficiency is 40.0 %?Give your answer in kJ.
A heat engine receives heat in the amount of Qh= 525 kJ from a high temperature thermal reservoir and delivers W,
net= 360 kJ of work
per cycle.
Write an expression for the efficiency of the engine.
What is this efficiency?
n =
Write an expression for the amount of energy required to be rejected into the low temperature reservoir.
How much energy, in kilojoules, is rejected into the low temperature resevoir?
Question 6. in one cycle, a heat engine does 700J of work and releases 1450 J of heat to a lower-temperature reservoir. What is the efficiency of this engine, in percent?
Chapter 21 Solutions
Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (4th Edition)
Ch. 21 - Prob. 1CQCh. 21 - Rank in order, from largest to smallest, the...Ch. 21 - Prob. 3CQCh. 21 - FIGURE Q21.4 shows the pV diagram of a heat...Ch. 21 - Rank in order, from largest to smallest, the...Ch. 21 - FIGURE Q21.6 shows the thermodynamic cycles of two...Ch. 21 - A heat engine satisfies Wout= Qnet. Why is there...Ch. 21 - Prob. 8CQCh. 21 - Prob. 9CQCh. 21 - Prob. 10CQ
Ch. 21 - Prob. 11CQCh. 21 - Prob. 1EAPCh. 21 - Prob. 2EAPCh. 21 - Prob. 3EAPCh. 21 - Prob. 4EAPCh. 21 - Prob. 5EAPCh. 21 - Prob. 6EAPCh. 21 - The power output of a car engine running at 2400...Ch. 21 - Prob. 8EAPCh. 21 - Prob. 9EAPCh. 21 - Prob. 10EAPCh. 21 - Prob. 11EAPCh. 21 - Prob. 12EAPCh. 21 - Prob. 13EAPCh. 21 - Prob. 14EAPCh. 21 - Prob. 15EAPCh. 21 - Prob. 16EAPCh. 21 - A heat engine uses a diatomic gas in a Brayton...Ch. 21 - At what pressure ratio does a Brayton cycle using...Ch. 21 - Prob. 19EAPCh. 21 - Prob. 20EAPCh. 21 - Prob. 21EAPCh. 21 - Prob. 22EAPCh. 21 - Prob. 23EAPCh. 21 - Prob. 24EAPCh. 21 - Prob. 25EAPCh. 21 - Prob. 26EAPCh. 21 - Prob. 27EAPCh. 21 - A Carnot engine whose hot-reservoir temperature is...Ch. 21 - Prob. 29EAPCh. 21 - A heat engine operating between energy reservoirs...Ch. 21 - Prob. 31EAPCh. 21 - A Carnot refrigerator operating between —20°C and...Ch. 21 - The coefficient of performance of a refrigerator...Ch. 21 - A Carnot heat engine with thermal efficiency 1/3...Ch. 21 - Prob. 35EAPCh. 21 - Prob. 36EAPCh. 21 - A heat engine with 50% of the Carnot efficiency...Ch. 21 - Prove that the work done in an adiabatic process i...Ch. 21 - Prob. 39EAPCh. 21 - Prob. 40EAPCh. 21 - An ideal refrigerator utilizes a Carnot cycle...Ch. 21 - Prob. 42EAPCh. 21 - There has long been an interest in using the vast...Ch. 21 - A Carnot heat engine operates between reservoirs...Ch. 21 - A Carnot engine operates between temperatures of...Ch. 21 - Prob. 46EAPCh. 21 - A Carnot heat engine and an ordinary refrigerator...Ch. 21 - 48. A heat engine running backward is called a...Ch. 21 - 49. A car's internal combustion engine can be...Ch. 21 - Prob. 50EAPCh. 21 - Prob. 51EAPCh. 21 - Prob. 52EAPCh. 21 - Prob. 53EAPCh. 21 - Prob. 54EAPCh. 21 - Prob. 55EAPCh. 21 - Prob. 56EAPCh. 21 - Prob. 57EAPCh. 21 - A heat engine using a monatomic gas follows the...Ch. 21 - Prob. 59EAPCh. 21 - Prob. 60EAPCh. 21 - Prob. 61EAPCh. 21 - Prob. 62EAPCh. 21 - Prob. 63EAPCh. 21 - Prob. 64EAPCh. 21 - Prob. 65EAPCh. 21 - Prob. 66EAPCh. 21 - Prob. 67EAPCh. 21 - Prob. 68EAPCh. 21 - Prob. 69EAPCh. 21 - Prob. 70EAPCh. 21 - A refrigerator using helium gas operates on the...Ch. 21 - Prob. 72EAPCh. 21 - The gasoline engine in your car can be modeled as...Ch. 21 - Prob. 74EAP
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- 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_forwardAn engine absorbs three times as much heat as it discharges. The work done by the engine per cycle is 50 J. Calculate (a) the efficiency of the engine, (b) the heat absorbed per cycle, and (c) the heat discharged per cycle.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
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