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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Question
Chapter 11, Problem 5P
To determine
To find: How many LEDs must be combined to give a total of 1.6 W of visible light output.
To determine
To find: The total power required to run LED light source.
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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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