Student Workbook for College Physics: A Strategic Approach
3rd Edition
ISBN: 9780321907240
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Question
Chapter 11, Problem 4P
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
Student Workbook for College Physics: A Strategic Approach
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 - For most automobiles, the number of miles per...Ch. 11 - A glassblower heats up a blob of glass in a...Ch. 11 - When the space shuttle returns to earth, its...Ch. 11 - Prob. 8CQCh. 11 - Prob. 9CQCh. 11 - A 20 kg block of steel at 23C and a 150 g piece of...
Ch. 11 - Prob. 11CQCh. 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 - A fire pistonan impressive physics...Ch. 11 - Prob. 19CQCh. 11 - A drop of green ink falls into a beaker of clear...Ch. 11 - Prob. 21CQCh. 11 - Prob. 22CQCh. 11 - According to the second law of thermodynamics, it...Ch. 11 - Assuming improved materials and better processes,...Ch. 11 - Electric vehicles increase speed by using an...Ch. 11 - When the suns light hits the earth, the...Ch. 11 - When you put an ice cube tray filled with liquid...Ch. 11 - Prob. 28CQCh. 11 - A person is walking on level ground at constant...Ch. 11 - A person walks 1 km, turns around, and runs back...Ch. 11 - Prob. 31MCQCh. 11 - 200 J of heat is added to two gases, each in a...Ch. 11 - An inventor approaches you with a device that he...Ch. 11 - Prob. 34MCQCh. 11 - Prob. 35MCQCh. 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 - A fast-food hamburger (with cheese and bacon)...Ch. 11 - In an average human, basic life processes require...Ch. 11 - An energy bar contains 6.0 g of fat. How much...Ch. 11 - An energy bar contains 22 g of carbohydrates. How...Ch. 11 - Prob. 9PCh. 11 - An energy bar contains 22 g of carbohydrates. If...Ch. 11 - Suppose your body was able to use the chemical...Ch. 11 - The label on a candy bar says 400 Calories....Ch. 11 - A weightlifter curls a 30 kg bar, raising it each...Ch. 11 - Prob. 14PCh. 11 - Prob. 15PCh. 11 - The planet Mercurys surface temperature varies...Ch. 11 - A piece of metal at 100C has its Celsius...Ch. 11 - Prob. 18PCh. 11 - 500 J of work are done on a system in a process...Ch. 11 - 600 J of heat energy are transferred to a system...Ch. 11 - 300 J of energy are transferred to a system in the...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 heat engine does 200 J of work while exhausting...Ch. 11 - A heat engine with an efficiency of 40% does 100 J...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 - Converting sunlight to electricity with solar...Ch. 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 - Find the maximum possible coefficient of...Ch. 11 - Which, if any, of the heat engines in Figure...Ch. 11 - Which, if any, of the refrigerators in Figure...Ch. 11 - Prob. 37PCh. 11 - Prob. 38GPCh. 11 - Prob. 39GPCh. 11 - For how long would a 68 kg athlete have to swim at...Ch. 11 - a. How much metabolic energy is required for a 68...Ch. 11 - Prob. 42GPCh. 11 - Prob. 43GPCh. 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 - A 70 kg student consumes 2500 Cal each day and...Ch. 11 - To make your workouts more productive, you can get...Ch. 11 - The resistance of an exercise bike is often...Ch. 11 - Prob. 50GPCh. 11 - Prob. 51GPCh. 11 - A large horse can perform work at a steady rate of...Ch. 11 - A heat engine with a high-temperature reservoir at...Ch. 11 - An engine does 10 J of work and exhausts 15 J of...Ch. 11 - The heat exhausted to the cold reservoir of an...Ch. 11 - An engine operating at maximum theoretical...Ch. 11 - Some heat engines can run on very small...Ch. 11 - The coefficient of performance of a refrigerator...Ch. 11 - An engineer claims to have measured the...Ch. 11 - A 32% efficient electric power plant produces 900...Ch. 11 - A typical coal-fired power plant burns 300 metric...Ch. 11 - Each second, a nuclear power plant generates 2000...Ch. 11 - Prob. 63GPCh. 11 - Prob. 64GPCh. 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 - MCAT-Style Passage Problems Kangaroo Locomotion...Ch. 11 - MCAT-Style Passage Problems Kangaroo Locomotion...Ch. 11 - MCAT-Style Passage Problems Kangaroo Locomotion...Ch. 11 - MCAT-Style Passage Problems Kangaroo Locomotion...Ch. 11 - MCAT-Style Passage Problems Kangaroo Locomotion...
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