Physics of Everyday Phenomena
9th Edition
ISBN: 9781259894008
Author: W. Thomas Griffith, Juliet Brosing Professor
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 11, Problem 1SP
Suppose that a typical automobile engine operates at an efficiency of 19%. One gallon of gasoline releases approximately 120 MJ of heat when it is burned. (A megajoule, MJ, is a million joules.)
a. Of the energy available in a gallon of gas, how much energy can be used to do useful work in moving the automobile and running its accessories?
b. How much heat per gallon is released to the environment in the exhaust gases and via the
c. If the car is moving at constant speed, how is the work output of the engine used?
d. Would you expect the efficiency of the engine to be greater on a very hot day or on a cold day? Explain. (There may be competing effects at work.)
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Chapter 11 Solutions
Physics of Everyday Phenomena
Ch. 11 - Prob. 1CQCh. 11 - Prob. 2CQCh. 11 - In applying the first law of thermodynamics to a...Ch. 11 - Is the total amount of heat released by a heat...Ch. 11 - From the perspective of the first law of...Ch. 11 - Which motor in a hybrid vehiclethe electric or...Ch. 11 - Prob. 7CQCh. 11 - Prob. 8CQCh. 11 - Prob. 9CQCh. 11 - Prob. 10CQ
Ch. 11 - Prob. 11CQCh. 11 - Is it possible for the efficiency of a heat engine...Ch. 11 - Can a Carnot engine operate in an irreversible...Ch. 11 - Does a gasoline-burning automobile engine operate...Ch. 11 - Which would have the greater efficiencya Carnot...Ch. 11 - If we want to increase the efficiency of a Carnot...Ch. 11 - Is a heat pump the same thing as a heat engine?...Ch. 11 - Is a heat pump essentially the same thing as a...Ch. 11 - When a heat pump is used to heat a building, where...Ch. 11 - Is it possible to cool a closed room by leaving...Ch. 11 - Prob. 21CQCh. 11 - Prob. 22CQCh. 11 - Prob. 23CQCh. 11 - Prob. 24CQCh. 11 - Which has the higher entropy, a deck of cards in...Ch. 11 - A hot cup of coffee is allowed to cool down, thus...Ch. 11 - When a substance freezes, the molecules become...Ch. 11 - Which would normally have the greater thermal...Ch. 11 - In what ways is a nuclear power plant similar to a...Ch. 11 - What is the distinction between high-grade heat...Ch. 11 - Prob. 31CQCh. 11 - Prob. 32CQCh. 11 - Is an automobile engine a perpetual-motion...Ch. 11 - Prob. 34CQCh. 11 - Prob. 35CQCh. 11 - The water draining from the bottom of the pond...Ch. 11 - Prob. 37CQCh. 11 - In one cycle, a heat engine takes in 1200 J of...Ch. 11 - A heat engine with an efficiency of 28% does 700 J...Ch. 11 - In one cycle, a heat engine takes in 800 J of heat...Ch. 11 - A heat engine with an efficiency of 35% takes in...Ch. 11 - In one cycle, a heat engine does 700 J of work and...Ch. 11 - A Carnot engine takes in heat at a temperature of...Ch. 11 - A Carnot engine takes in heat from a reservoir at...Ch. 11 - A Carnot engine operates between temperatures of...Ch. 11 - A heat pump takes in 450 J of heat from a...Ch. 11 - In each cycle of its operation, a refrigerator...Ch. 11 - A typical electric refrigerator (see fig. 11.9)...Ch. 11 - A typical nuclear power plant delivers heat from...Ch. 11 - An ocean thermal-energy power plant takes in warm...Ch. 11 - An engineer designs a heat engine using flat-plate...Ch. 11 - Suppose that a typical automobile engine operates...Ch. 11 - Prob. 2SPCh. 11 - A Carnot engine operating in reverse as a heat...Ch. 11 - In section 11.3, we showed that a violation of the...Ch. 11 - Suppose that an oil-fired power plant is designed...
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