Physics for Scientists and Engineers, Technology Update (No access codes included)
9th Edition
ISBN: 9781305116399
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 22, Problem 22.62AP
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, Technology Update (No access codes included)
Ch. 22 - The energy input to an engine is 4.00 times...Ch. 22 - The energy entering an electric heater by...Ch. 22 - Three engines operate between reservoirs separated...Ch. 22 - (a) Suppose you select four cards at random from a...Ch. 22 - An ideal gas is taken from an initial temperature...Ch. 22 - True or False: The entropy change in an adiabatic...Ch. 22 - The second law of thermodynamics implies that the...Ch. 22 - Assume a sample of an ideal gas is at room...Ch. 22 - A refrigerator has 18.0 kJ of work clone on it...Ch. 22 - Of the following, which is not a statement of the...
Ch. 22 - Consider cyclic processes completely characterized...Ch. 22 - Prob. 22.6OQCh. 22 - A steam turbine operates at a boiler temperature...Ch. 22 - A thermodynamic process occurs in which the...Ch. 22 - A sample of a monatomic ideal gas is contained in...Ch. 22 - An engine does 15.0 kJ of work while exhausting...Ch. 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. 22.3CQCh. 22 - The first law of thermodynamics says you cant...Ch. 22 - Energy is the mistress of the Universe, and...Ch. 22 - Prob. 22.6CQCh. 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. 22.10CQCh. 22 - Prob. 22.11CQCh. 22 - (a) If you shake a jar full of jelly beans of...Ch. 22 - Prob. 22.13CQCh. 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 - An engine absorbs 1.70 kJ from a hot reservoir at...Ch. 22 - A multicylinder gasoline engine in an airplane,...Ch. 22 - Suppose a heat engine is connected to two energy...Ch. 22 - A refrigerator has a coefficient of performance...Ch. 22 - During each cycle, a refrigerator ejects 625 kJ of...Ch. 22 - A heat pump has a coefficient of performance of...Ch. 22 - A refrigerator has a coefficient of performance of...Ch. 22 - A heat pump has a coefficient of performance equal...Ch. 22 - A freezer has a coefficient of performance of...Ch. 22 - Prob. 22.14PCh. 22 - One of the most efficient heat engines ever built...Ch. 22 - Why is the following situation impossible? An...Ch. 22 - A Carnot engine has a power output of 150 kW. The...Ch. 22 - A Carnot engine has a power output P. The engine...Ch. 22 - What is the coefficient of performance of a...Ch. 22 - An ideal refrigerator or ideal heat pump is...Ch. 22 - Prob. 22.21PCh. 22 - How much work does an ideal Carnot refrigerator...Ch. 22 - If a 35.0% -efficient Carnot heat engine (Fig....Ch. 22 - A power plant operates at a 32.0% efficiency...Ch. 22 - A heat engine is being designed to have a Carnot...Ch. 22 - A Carnot heat engine operates between temperatures...Ch. 22 - An ideal gas is taken through a Carnot cycle. The...Ch. 22 - Prob. 22.28PCh. 22 - Prob. 22.29PCh. 22 - Suppose you build a two-engine device with the...Ch. 22 - Argon enters a turbine at a rate of 80.0 kg/min, a...Ch. 22 - At point A in a Carnot cycle, 2.34 mol of a...Ch. 22 - An electric generating station is designed to have...Ch. 22 - An ideal (Carnot) freezer in a kitchen has a...Ch. 22 - A heat pump used for heating shown in Figure...Ch. 22 - A gasoline engine has a compression ratio of 6.00....Ch. 22 - In a cylinder of an automobile engine, immediately...Ch. 22 - An idealized diesel engine operates in a cycle...Ch. 22 - Prob. 22.39PCh. 22 - (a) Prepare a table like Table 21.1 for the...Ch. 22 - Prob. 22.41PCh. 22 - An ice tray contains 500 g of liquid water at 0C....Ch. 22 - A Styrofoam cup holding 125 g of hot water at 100C...Ch. 22 - A 1.00-kg iron horseshoe is taken from a forge at...Ch. 22 - A 1 500-kg car is moving at 20.0 m/s. The driver...Ch. 22 - Prob. 22.46PCh. 22 - Prob. 22.47PCh. 22 - 1.00-mol sample of H2 gas is contained in the left...Ch. 22 - A 2.00-L container has a center partition that...Ch. 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 - How fast are you personally making the entropy of...Ch. 22 - When an aluminum bar is connected between a hot...Ch. 22 - When a metal bar is connected between a hot...Ch. 22 - Prob. 22.55PCh. 22 - Calculate the increase in entropy of the Universe...Ch. 22 - How much work is required, using an ideal Carnot...Ch. 22 - Prob. 22.58APCh. 22 - The energy absorbed by an engine is three times...Ch. 22 - Prob. 22.60APCh. 22 - Prob. 22.61APCh. 22 - In 1993, the U.S. government instituted a...Ch. 22 - Prob. 22.63APCh. 22 - One mole of neon gas is heated from 300 K to 420 K...Ch. 22 - Au airtight freezer holds n moles of air at 25.0C...Ch. 22 - Suppose an ideal (Carnot) heat pump could be...Ch. 22 - In 1816, Robert Stirling, a Scottish clergyman,...Ch. 22 - A firebox is at 750 K, and the ambient temperature...Ch. 22 - Review. 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