EBK THERMODYNAMICS: AN ENGINEERING APPR
8th Edition
ISBN: 9780100257054
Author: CENGEL
Publisher: YUZU
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Chapter 6.11, Problem 45P
When a man returns to his well-sealed house on a summer day, he finds that the house is at 35°C. He turns on the air conditioner, which cools the entire house to 20°C in 30 min. If the COP of the air-conditioning system is 2.8, determine the power drawn by the air conditioner. Assume the entire mass within the house is equivalent to 800 kg of air for which cV = 0.72 kJ/kg·°C and cp = 1.0 kJ/kg·°C.
FIGURE P6–50
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Chapter 6 Solutions
EBK THERMODYNAMICS: AN ENGINEERING APPR
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Ch. 6.11 - Does a heat engine that has a thermal efficiency...Ch. 6.11 - In the absence of any friction and other...Ch. 6.11 - Are the efficiencies of all the work-producing...Ch. 6.11 - Consider a pan of water being heated (a) by...Ch. 6.11 - Prob. 15PCh. 6.11 - Prob. 16PCh. 6.11 - A heat engine has a heat input of 3 104 Btu/h and...Ch. 6.11 - Prob. 18PCh. 6.11 - A 600-MW steam power plant, which is cooled by a...Ch. 6.11 - Prob. 20PCh. 6.11 - A heat engine with a thermal efficiency of 45...Ch. 6.11 - A steam power plant with a power output of 150 MW...Ch. 6.11 - An automobile engine consumes fuel at a rate of 22...Ch. 6.11 - Prob. 24PCh. 6.11 - Prob. 25PCh. 6.11 - A coal-burning steam power plant produces a net...Ch. 6.11 - An Ocean Thermal Energy Conversion (OTEC) power...Ch. 6.11 - What is the difference between a refrigerator and...Ch. 6.11 - Prob. 29PCh. 6.11 - In a refrigerator, heat is transferred from a...Ch. 6.11 - A heat pump is a device that absorbs energy from...Ch. 6.11 - Define the coefficient of performance of a...Ch. 6.11 - Define the coefficient of performance of a heat...Ch. 6.11 - Prob. 34PCh. 6.11 - A refrigerator has a COP of 1.5. That is, the...Ch. 6.11 - What is the Clausius expression of the second law...Ch. 6.11 - Show that the KelvinPlanck and the Clausius...Ch. 6.11 - Prob. 38PCh. 6.11 - Determine the COP of a heat pump that supplies...Ch. 6.11 - Prob. 40PCh. 6.11 - Prob. 41PCh. 6.11 - 6–42 An air conditioner removes heat steadily from...Ch. 6.11 - 6–43 A food department is kept at –12°C by a...Ch. 6.11 - A household refrigerator that has a power input of...Ch. 6.11 - When a man returns to his well-sealed house on a...Ch. 6.11 - Prob. 47PCh. 6.11 - Prob. 48PCh. 6.11 - 6–49 A heat pump is used to maintain a house at a...Ch. 6.11 - Prob. 50PCh. 6.11 - A household refrigerator runs one-fourth of the...Ch. 6.11 - Prob. 52PCh. 6.11 - Consider an office room that is being cooled...Ch. 6.11 - Prob. 54PCh. 6.11 - Refrigerant-134a enters the condenser of a...Ch. 6.11 - An inventor claims to have developed a resistance...Ch. 6.11 - Prob. 57PCh. 6.11 - A cold canned drink is left in a warmer room where...Ch. 6.11 - A block slides down an inclined plane with...Ch. 6.11 - 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In an effort to conserve energy in a heat-engine...Ch. 6.11 - Prob. 88PCh. 6.11 - Prob. 89PCh. 6.11 - 6–90 During an experiment conducted in a room at...Ch. 6.11 - Prob. 91PCh. 6.11 - An air-conditioning system operating on the...Ch. 6.11 - Prob. 93PCh. 6.11 - Prob. 94PCh. 6.11 - Prob. 95PCh. 6.11 - Prob. 96PCh. 6.11 - 6–97 A heat pump is used to maintain a house at...Ch. 6.11 - Prob. 98PCh. 6.11 - Prob. 99PCh. 6.11 - Prob. 100PCh. 6.11 - A commercial refrigerator with refrigerant-134a as...Ch. 6.11 - Prob. 102PCh. 6.11 - A heat pump is to be used for heating a house in...Ch. 6.11 - A Carnot heat pump is to be used to heat a house...Ch. 6.11 - A Carnot heat engine receives heat from a...Ch. 6.11 - Prob. 106PCh. 6.11 - Prob. 107PCh. 6.11 - Prob. 108PCh. 6.11 - Derive an expression for the COP of a completely...Ch. 6.11 - Prob. 110PCh. 6.11 - Prob. 111PCh. 6.11 - Prob. 112PCh. 6.11 - Prob. 113PCh. 6.11 - Someone proposes that the entire...Ch. 6.11 - Prob. 115PCh. 6.11 - Prob. 116PCh. 6.11 - Prob. 117PCh. 6.11 - It is often stated that the refrigerator door...Ch. 6.11 - Prob. 119RPCh. 6.11 - A Carnot heat pump is used to heat and maintain a...Ch. 6.11 - Prob. 121RPCh. 6.11 - Prob. 122RPCh. 6.11 - A refrigeration system uses a water-cooled...Ch. 6.11 - A heat pump with a COP of 2.8 is used to heat an...Ch. 6.11 - Prob. 125RPCh. 6.11 - Consider a Carnot refrigeration cycle executed in...Ch. 6.11 - Consider two Carnot heat engines operating in...Ch. 6.11 - Prob. 129RPCh. 6.11 - A heat engine operates between two reservoirs at...Ch. 6.11 - Prob. 132RPCh. 6.11 - An old gas turbine has an efficiency of 21 percent...Ch. 6.11 - Prob. 134RPCh. 6.11 - Prob. 135RPCh. 6.11 - Prob. 136RPCh. 6.11 - Prob. 137RPCh. 6.11 - Prob. 138RPCh. 6.11 - Prob. 139RPCh. 6.11 - A refrigeration system is to cool bread loaves...Ch. 6.11 - The drinking water needs of a production facility...Ch. 6.11 - Prob. 143RPCh. 6.11 - Prob. 145RPCh. 6.11 - Prob. 146RPCh. 6.11 - Prob. 147RPCh. 6.11 - Prob. 148RPCh. 6.11 - 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