College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Chapter 11, Problem 7CQ
For most automobiles, the number of miles per gallon decreases as highway speed increases. Fuel economy drops as speeds increase from 55 to 65 mph, then decreases further as speeds increase to 75 mph. Explain why this is the case.
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Chapter 11 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 11 - Rub your hands together vigorously. What happens?...Ch. 11 - Describe the energy transfers and transformations...Ch. 11 - According to Table 11.4, cycling at 15 km/h...Ch. 11 - Prob. 4CQCh. 11 - Prob. 5CQCh. 11 - For most automobiles, the number of miles per...Ch. 11 - Prob. 8CQCh. 11 - Prob. 9CQCh. 11 - Prob. 10CQCh. 11 - Prob. 11CQ
Ch. 11 - Prob. 12CQCh. 11 - For Questions 12 through 17, give a specific...Ch. 11 - For Questions 12 through 17, give a specific...Ch. 11 - For Questions 12 through 17, give a specific...Ch. 11 - For Questions 12 through 17, give a specific...Ch. 11 - For Questions 12 through 17, give a specific...Ch. 11 - For Questions 12 through 17, give a specific...Ch. 11 - Prob. 19CQCh. 11 - Prob. 20CQCh. 11 - Prob. 21CQCh. 11 - Prob. 22CQCh. 11 - Prob. 24CQCh. 11 - Prob. 25CQCh. 11 - Electric vehicles increase speed by using an...Ch. 11 - When the suns light hits the earth, the...Ch. 11 - Prob. 29CQCh. 11 - Prob. 30CQCh. 11 - Prob. 31CQCh. 11 - Prob. 32MCQCh. 11 - Prob. 33MCQCh. 11 - A person is walking on level ground at constant...Ch. 11 - A person walks 1 km, turns around, and runs back...Ch. 11 - 200 J of heat is added to two gases, each in a...Ch. 11 - Prob. 37MCQCh. 11 - A refrigerators freezer compartment is set at 10C;...Ch. 11 - A 10% efficient engine accelerates a 1500 kg car...Ch. 11 - Prob. 2PCh. 11 - A typical photovoltaic cell delivers 4.0 103 W of...Ch. 11 - Prob. 4PCh. 11 - Prob. 5PCh. 11 - Prob. 6PCh. 11 - In an average human, basic life processes require...Ch. 11 - Prob. 8PCh. 11 - An energy bar contains 22 g of carbohydrates. How...Ch. 11 - Prob. 10PCh. 11 - Prob. 11PCh. 11 - Prob. 12PCh. 11 - An energy bar contains 22 g of carbohydrates. If...Ch. 11 - Prob. 14PCh. 11 - Prob. 15PCh. 11 - Prob. 16PCh. 11 - The label on a candy bar says 400 Calories....Ch. 11 - Prob. 18PCh. 11 - A weightlifter curls a 30 kg bar, raising it each...Ch. 11 - Prob. 20PCh. 11 - Prob. 21PCh. 11 - Prob. 22PCh. 11 - Suppose your body was able to use the chemical...Ch. 11 - Prob. 24PCh. 11 - Prob. 25PCh. 11 - Prob. 26PCh. 11 - Prob. 27PCh. 11 - The planet Mercurys surface temperature varies...Ch. 11 - A piece of metal at 100C has its Celsius...Ch. 11 - Prob. 30PCh. 11 - 500 J of work are done on a system in a process...Ch. 11 - Prob. 32PCh. 11 - 600 J of heat energy are transferred to a system...Ch. 11 - 10 J of heat are removed from a gas sample while...Ch. 11 - A heat engine extracts 55 kJ from the hot...Ch. 11 - A heat engine does 20 J of work while exhausting...Ch. 11 - A power plant running at 35% efficiency generates...Ch. 11 - A heat engine operating between energy reservoirs...Ch. 11 - A newly proposed device for generating electricity...Ch. 11 - Prob. 41PCh. 11 - Prob. 42PCh. 11 - Prob. 43PCh. 11 - Prob. 44PCh. 11 - A refrigerator takes in 20 J of work and exhausts...Ch. 11 - Air conditioners are rated by their coefficient of...Ch. 11 - 50 J of work are done on a refrigerator with a...Ch. 11 - Prob. 48PCh. 11 - Find the maximum possible coefficient of...Ch. 11 - Prob. 50PCh. 11 - Prob. 51PCh. 11 - Prob. 52PCh. 11 - Prob. 53PCh. 11 - Prob. 55GPCh. 11 - Prob. 56GPCh. 11 - The record time for a Tour de France cyclist to...Ch. 11 - Championship swimmers take about 22 s and about 30...Ch. 11 - A 68 kg hiker walks at 5.0 km/h up a 7% slope....Ch. 11 - To make your workouts more productive, you can get...Ch. 11 - The resistance of an exercise bike is often...Ch. 11 - Prob. 62GPCh. 11 - Prob. 63GPCh. 11 - An engine does 10 J of work and exhausts 15 J of...Ch. 11 - An engine operating at maximum theoretical...Ch. 11 - An engineer claims to have measured the...Ch. 11 - A typical coal-fired power plant burns 300 metric...Ch. 11 - Prob. 68GPCh. 11 - Air conditioners sold in the United States are...Ch. 11 - The surface waters of tropical oceans are at a...Ch. 11 - The light energy that falls on a square meter of...Ch. 11 - Prob. 72MSPPCh. 11 - Prob. 73MSPPCh. 11 - Prob. 74MSPPCh. 11 - Prob. 75MSPPCh. 11 - Prob. 76MSPPCh. 11 - Prob. 77MSPPCh. 11 - Prob. 78MSPPCh. 11 - Prob. 79MSPP
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