College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
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Textbook Question
Chapter 15, Problem 33PE
A coal−fired electrical power station has an efficiency of 38%. The temperature of the steam leaving the boiler is 550°C. What percentage of the maximum efficiency does this station obtain? (Assume the temperature of the environment is
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Chapter 15 Solutions
College Physics
Ch. 15 - Describe the photo of the tea kettle at the...Ch. 15 - The first law of thermodynamics and the...Ch. 15 - Heat transfer Q and work done W are always energy...Ch. 15 - How do heat transfer and internal energy differ?...Ch. 15 - If you run down some stairs and stop, what happens...Ch. 15 - Give an explanation of how food energy (calories)...Ch. 15 - Identify the type of energy transferred to your...Ch. 15 - A great deal of effort time, and money has been...Ch. 15 - One method of converting heat transfer to doing...Ch. 15 - Would the previous question make any sense for an...
Ch. 15 - We ordinarily say that U=0 for an isothermal...Ch. 15 - The temperature of a rapidly expanding gas...Ch. 15 - Which cyclical process represented by the two...Ch. 15 - A real process may be nearly adiabatic if it...Ch. 15 - It is unlikely that a process can be isothermal...Ch. 15 - Imagine you are driving a car up Pike’s Peak in...Ch. 15 - Is a temperature difference necessary to operate a...Ch. 15 - Definitions of efficiency vary depending on how...Ch. 15 - Whyother than the fact that the second law of...Ch. 15 - Think about the drinking bird at the beginning of...Ch. 15 - Can improved engineering and materials be employed...Ch. 15 - Does the second law of thermodynamics alter the...Ch. 15 - Explain why heat pumps do not work as well in very...Ch. 15 - In some Northern European nations, homes are being...Ch. 15 - Why do refrigerators, air conditioners, and heat...Ch. 15 - Grocery store managers contend that there is less...Ch. 15 - Can you cool a kitchen by leaving the refrigerator...Ch. 15 - A woman shuts her summer cottage up in September...Ch. 15 - Consider a system with a certain energy content,...Ch. 15 - Does a gas become more orderly when it liquefies?...Ch. 15 - Explain how water’s entropy can decrease when it...Ch. 15 - Is a uniform-temperature gas more or less orderly...Ch. 15 - Give an example of a spontaneous process in which...Ch. 15 - What is the change in entropy in an adiabatic...Ch. 15 - Does the entropy at a star increase or decrease as...Ch. 15 - Explain why a building made of bricks has smaller...Ch. 15 - Explain why a building made of bricks has smaller...Ch. 15 - What is the change in internal energy of a car if...Ch. 15 - How much heat transfer occurs from a system, if...Ch. 15 - A system does 1.80108J of work while 7.50108J of...Ch. 15 - What is the change in internal energy of a system...Ch. 15 - Suppose a woman does 500 J of work and 9500 J of...Ch. 15 - (a) How much food energy will a man metabolize in...Ch. 15 - (a) What is the average metabolic rate in watts of...Ch. 15 - (a) How long will the energy in a 1470kJ (350kcal)...Ch. 15 - (a) A woman climbing the Washington Monument...Ch. 15 - A car tire contains 0.0380m3 S of air at a...Ch. 15 - A heliumfilled toy balloon has a gauge pressure of...Ch. 15 - Steam to drive an old—fashioned steam locomotive...Ch. 15 - A hand—driven tire pump has a piston with a 2.50cm...Ch. 15 - Calculate the net work output of a heat engine...Ch. 15 - What is the net work output of a heat engine that...Ch. 15 - Unreasonable Results What is wrong with the claim...Ch. 15 - (a) A cyclical heat engine, operating between...Ch. 15 - Construct Your Own Problem Consider a car's...Ch. 15 - Construct Your Own Problem Consider a car trip...Ch. 15 - A certain heat engine does 10.0 kJ of work and...Ch. 15 - With 2.56106J of heat transfer into this engine, a...Ch. 15 - (a) What is the work output of a cyclical heat...Ch. 15 - (a) What is the eficiency of a cyclical heat...Ch. 15 - The engine of a large Ship does 2.00108J of work...Ch. 15 - 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Suppose you want to operate an ideal refrigerator...Ch. 15 - An ideal heat pump is being considered for use in...Ch. 15 - A 4ton air conditioner removes 5.60107J (48,000...Ch. 15 - Show that the coefficients of performance of...Ch. 15 - (a) On a winter day, a certain house loses...Ch. 15 - On a hot summer day, 4.00106J of heat transfer...Ch. 15 - A hot rock ejected from a volcano's lava fountain...Ch. 15 - When 1.60105J of heat transfer occurs into a meat...Ch. 15 - The Sun radiates energy at the rate of 3.801026W...Ch. 15 - (a) In reaching equilibrium, how much heat...Ch. 15 - What is the decrease in entropy of 25.0 g of water...Ch. 15 - Find the increase in entropy of 1.00 kg of liquid...Ch. 15 - A large electrical power station generates 1000 MW...Ch. 15 - (a) How much heat transfer occurs from 20.0 kg of...Ch. 15 - Using Table 15.4, verify the contention that if...Ch. 15 - What percent of the time will you get something in...Ch. 15 - (a) If tossing 100 coins, how many ways...Ch. 15 - 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