Physics for Scientists and Engineers With Modern Physics
9th Edition
ISBN: 9781133953982
Author: SERWAY, Raymond A./
Publisher: Cengage Learning
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Chapter 22, Problem 62AP
In 1993, the U.S. government instituted a requirement that all room air conditioners sold in the United States must have an energy efficiency ratio (EER) of 10 or higher. The EER is defined as the ratio of the cooling capacity of the air conditioner, measured in British thermal units per hour, or Btu/h, to its electrical power requirement in watts. (a) Convert the EER of 10.0 to dimensionless form, using the conversion 1 Btu = 1 055 J. (b) What is the appropriate name for this dimensionless quantity? (c) In the 1970s, it was common to find room air conditioners with EERs of 5 or lower. State how the operating costs compare for 10 000-Btu/h air conditioners with EERs of 5.00 and 10.0. Assume each air conditioner operates for 1 500 h during the summer in a city where electricity costs 17.0¢ per kWh.
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Chapter 22 Solutions
Physics for Scientists and Engineers With Modern Physics
Ch. 22.1 - The energy input to an engine is 4.00 times...Ch. 22.2 - The energy entering an electric heater by...Ch. 22.4 - Three engines operate between reservoirs separated...Ch. 22.6 - (a) Suppose you select four cards at random from a...Ch. 22.7 - An ideal gas is taken from an initial temperature...Ch. 22.7 - True or False: The entropy change in an adiabatic...Ch. 22 - Prob. 1OQCh. 22 - Prob. 2OQCh. 22 - Prob. 3OQCh. 22 - Of the following, which is not a statement of the...
Ch. 22 - Prob. 5OQCh. 22 - Prob. 6OQCh. 22 - Prob. 7OQCh. 22 - Prob. 8OQCh. 22 - Prob. 9OQCh. 22 - Prob. 10OQCh. 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. 3CQCh. 22 - The first law of thermodynamics says you cant...Ch. 22 - Energy is the mistress of the Universe, and...Ch. 22 - (a) Give an example of an irreversible process...Ch. 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. 10CQCh. 22 - Prob. 11CQCh. 22 - (a) If you shake a jar full of jelly beans of...Ch. 22 - What are some factors that affect the efficiency...Ch. 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 - Prob. 5PCh. 22 - Prob. 6PCh. 22 - Suppose a heat engine is connected to two energy...Ch. 22 - Prob. 8PCh. 22 - During each cycle, a refrigerator ejects 625 kJ of...Ch. 22 - Prob. 10PCh. 22 - Prob. 11PCh. 22 - Prob. 12PCh. 22 - A freezer has a coefficient of performance of...Ch. 22 - Prob. 14PCh. 22 - One of the most efficient heat engines ever built...Ch. 22 - Prob. 16PCh. 22 - Prob. 17PCh. 22 - Prob. 18PCh. 22 - Prob. 19PCh. 22 - Prob. 20PCh. 22 - Prob. 21PCh. 22 - How much work does an ideal Carnot refrigerator...Ch. 22 - Prob. 23PCh. 22 - A power plant operates at a 32.0% efficiency...Ch. 22 - Prob. 25PCh. 22 - Prob. 26PCh. 22 - Prob. 27PCh. 22 - Prob. 28PCh. 22 - A heat engine operates in a Carnot cycle between...Ch. 22 - Suppose you build a two-engine device with the...Ch. 22 - Prob. 31PCh. 22 - Prob. 32PCh. 22 - Prob. 33PCh. 22 - Prob. 34PCh. 22 - Prob. 35PCh. 22 - Prob. 36PCh. 22 - Prob. 37PCh. 22 - Prob. 38PCh. 22 - Prob. 39PCh. 22 - Prob. 40PCh. 22 - Prob. 41PCh. 22 - Prob. 42PCh. 22 - A Styrofoam cup holding 125 g of hot water at 100C...Ch. 22 - Prob. 44PCh. 22 - A 1 500-kg car is moving at 20.0 m/s. The driver...Ch. 22 - Prob. 46PCh. 22 - Prob. 47PCh. 22 - Prob. 48PCh. 22 - Prob. 49PCh. 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 - Prob. 52PCh. 22 - Prob. 53PCh. 22 - Prob. 54PCh. 22 - Prob. 55PCh. 22 - Prob. 56APCh. 22 - Prob. 57APCh. 22 - A steam engine is operated in a cold climate where...Ch. 22 - Prob. 59APCh. 22 - Prob. 60APCh. 22 - Prob. 61APCh. 22 - In 1993, the U.S. government instituted a...Ch. 22 - Prob. 63APCh. 22 - Prob. 64APCh. 22 - Prob. 65APCh. 22 - Prob. 66APCh. 22 - In 1816, Robert Stirling, a Scottish clergyman,...Ch. 22 - Prob. 68APCh. 22 - Prob. 69APCh. 22 - Prob. 70APCh. 22 - Prob. 71APCh. 22 - Prob. 72APCh. 22 - Prob. 73APCh. 22 - A system consisting of n moles of an ideal gas...Ch. 22 - A heat engine operates between two reservoirs at...Ch. 22 - Prob. 76APCh. 22 - Prob. 77APCh. 22 - Prob. 78APCh. 22 - A sample of an ideal gas expands isothermally,...Ch. 22 - Prob. 80APCh. 22 - Prob. 81CP
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