Physics (5th Edition)
5th Edition
ISBN: 9780321976444
Author: James S. Walker
Publisher: PEARSON
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Textbook Question
Chapter 18, Problem 48PCE
Predict/Calculate A portable generator produces 2.5 kW of mechanical work with an efficiency of 0.20 to supply electricity at a work site. (a) If the efficiency is increased but the work output remains the same, will the rate of fuel consumption by the engine increase, decrease, or stay the same? Explain. (b) Will the rate of waste heat emission increase, decrease, or stay the same? Explain. (c) Calculate the rates of fuel consumption and waste heat emission for engine efficiencies of 0.20 and 0.30.
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Answer b and c
4. Suppose that a nuclear power plant has an efficiency of about 0.34, and generates 1000
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plant, approximately 3 m deep, and flows at a rate of 0.5 m/s. Suppose that the plant
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the water, then returns the warmer water to the river. How much warmer is the river
downstream of the plant compared to upstream? Water's specific heat is approximately
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[Answer: The water is warmer by 4.62 K. This is a lot warmer!]
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Chapter 18 Solutions
Physics (5th Edition)
Ch. 18.1 - System 1 is at 0 C and system 2 is at 0 F. If...Ch. 18.2 - Enhance Your Understanding (Answers given at the...Ch. 18.3 - Enhance Your Understanding (Answers given at the...Ch. 18.4 - Enhance Your Understanding (Answers given at the...Ch. 18.5 - Enhance Your Understanding (Answers given at the...Ch. 18.6 - Enhance Your Understanding (Answers given at the...Ch. 18.7 - Enhance Your Understanding (Answers given at the...Ch. 18.8 - Enhance Your Understanding (Answers given at the...Ch. 18.9 - Enhance Your Understanding (Answers given at the...Ch. 18.10 - Enhance Your Understanding (Answer given at the...
Ch. 18 - Prob. 1CQCh. 18 - Heat is added to a substance. Is it safe to...Ch. 18 - Are there thermodynamic processes in which all the...Ch. 18 - An ideal gas is held in an insulated container at...Ch. 18 - Prob. 5CQCh. 18 - Which law of thermodynamics would be violated if...Ch. 18 - Heat engines always give off a certain amount of...Ch. 18 - Prob. 8CQCh. 18 - Which law of thermodynamics is most pertinent to...Ch. 18 - Which has more entropy: (a) popcorn kernels, or...Ch. 18 - Prob. 1PCECh. 18 - A gas expands, doing 100 J of work. How much heat...Ch. 18 - A swimmer does 7.7 105 J of work and gives off...Ch. 18 - When 1310 J of heat are added to one mole of an...Ch. 18 - Three different processes act on a system. (a) In...Ch. 18 - A container holds a gas consisting of 2.85 moles...Ch. 18 - The Charge on Adhesive Tape When adhesive tape is...Ch. 18 - Predict/Calculate One mole of an ideal monatomic...Ch. 18 - Prob. 9PCECh. 18 - A cylinder contains 4.0 moles of a monatomic gas...Ch. 18 - An ideal gas is taken through the three processes...Ch. 18 - Figure 18-26 shows three different multistep...Ch. 18 - Prob. 13PCECh. 18 - An ideal gas is compressed at constant pressure to...Ch. 18 - As an ideal gas expands at constant pressure from...Ch. 18 - A system consisting of an ideal gas at the...Ch. 18 - Prob. 17PCECh. 18 - (a) Find the work done by a monatomic ideal gas as...Ch. 18 - Prob. 19PCECh. 18 - Predict/Calculate If 9.50 moles of a monatomic...Ch. 18 - Suppose 118 moles of a monatomic ideal gas undergo...Ch. 18 - A weather balloon contains an ideal gas and has a...Ch. 18 - Prob. 23PCECh. 18 - During an adiabatic process, the temperature of...Ch. 18 - An ideal gas follows the three-part process shown...Ch. 18 - With the pressure held constant at 260 kPa, 43 mol...Ch. 18 - Prob. 27PCECh. 18 - A system expands by 0.75 m3 at a constant pressure...Ch. 18 - Prob. 29PCECh. 18 - A certain amount of a monatomic ideal gas...Ch. 18 - An ideal gas doubles its volume in one of three...Ch. 18 - Predict/Explain You plan to add a certain amount...Ch. 18 - Find the amount of heat needed to increase the...Ch. 18 - (a) If 585 J of heat are added to 49 moles of a...Ch. 18 - A system consists of 3.5 mol of an ideal monatomic...Ch. 18 - Find the change in temperature if 170 J of heat...Ch. 18 - Gasoline Ignition Consider a short time span just...Ch. 18 - Prob. 38PCECh. 18 - Prob. 39PCECh. 18 - A monatomic ideal gas is held in a thermally...Ch. 18 - Consider the expansion of 60.0 moles of a...Ch. 18 - A Carnot engine can be operated with one of the...Ch. 18 - What is the efficiency of an engine that exhausts...Ch. 18 - An engine receives 660 J of heat from a hot...Ch. 18 - A Carnot engine operates between the temperatures...Ch. 18 - A nuclear power plant has a reactor that produces...Ch. 18 - At a coal-burning power plant a steam turbine is...Ch. 18 - Predict/Calculate A portable generator produces...Ch. 18 - Predict/Calculate The efficiency of a particular...Ch. 18 - During each cycle a reversible engine absorbs 3100...Ch. 18 - Prob. 51PCECh. 18 - The operating temperatures for a Carnot engine are...Ch. 18 - A certain Carnot engine takes in the heat Qh and...Ch. 18 - Predict/Explain (a) If the temperature in the...Ch. 18 - The refrigerator in your kitchen does 490 J of...Ch. 18 - A refrigerator with a coefficient of performance...Ch. 18 - Prob. 57PCECh. 18 - Prob. 58PCECh. 18 - An air conditioner is used to keep the interior of...Ch. 18 - A reversible refrigerator has a coefficient of...Ch. 18 - A freezer has a coefficient of performance equal...Ch. 18 - Predict/Explain (a) If you rub your hands...Ch. 18 - Predict/Explain (a) An ideal gas is expanded...Ch. 18 - Predict/Explain (a) A gas is expanded reversibly...Ch. 18 - Find the change in entropy when 1.85 kg of water...Ch. 18 - Determine the change in entropy that occurs when...Ch. 18 - Prob. 67PCECh. 18 - On a cold winters day heat leaks slowly out of a...Ch. 18 - An 88-kg parachutist descends through a vertical...Ch. 18 - Predict/Calculate Consider the air-conditioning...Ch. 18 - A heat engine operates between a high-temperature...Ch. 18 - It can be shown that as a mass m with specific...Ch. 18 - Prob. 73GPCh. 18 - Figure 18-34 Problem 74 74 CE An ideal gas has...Ch. 18 - The heat that goes into a particular Carnot engine...Ch. 18 - Predict/Calculate Consider 132 moles of a...Ch. 18 - Prob. 77GPCh. 18 - Prob. 78GPCh. 18 - Predict/Calculate Engine A has an efficiency of...Ch. 18 - Nuclear Versus Natural Gas Energy Because of...Ch. 18 - A freezer with a coefficient of performance of...Ch. 18 - Entropy and the Sun The surface of the Sun has a...Ch. 18 - Prob. 83GPCh. 18 - A cylinder with a movable piston holds 2.95 mol of...Ch. 18 - Making Ice You place 0.410 kg of cold water inside...Ch. 18 - An inventor claims a new cyclic engine that uses...Ch. 18 - Predict/Calculate A small dish containing 530 g of...Ch. 18 - Predict/Calculate An ideal gas is taken through...Ch. 18 - One mole of an ideal monatomic gas follows the...Ch. 18 - When a heat Q is added to a monatomic ideal gas at...Ch. 18 - The Carnot Cycle Figure 18-36 shows an example of...Ch. 18 - A Carnot engine and a Carnot refrigerator operate...Ch. 18 - Prob. 93PPCh. 18 - Energy from the Ocean Whenever two objects are at...Ch. 18 - Prob. 95PPCh. 18 - Energy from me Ocean Whenever two objects are at...Ch. 18 - Predict/Calculate Referring to Example 18-21...Ch. 18 - Predict/Calculate Referring to Example 18-21...
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