1 Mass and Energy Use the equivalence of energy and rest mass, E = mc² to answer the following questions. (a) The total electrical energy generated in the United States is on the order of 10¹2 kWh per year. How much mass is this equivalent to? (b) The earth's orbital radius is about 1.5 × 10¹1 m. At this distance from the sun, the energy flux of sunlight is about 1.4 kW/m². How much mass does the sun radiate as light in one second? (c) A student pedaling a bicycle full throttle produces about one-half horsepower of useful power. (1 hp is equivalent to 746 W.) The human body is about 25 percent efficient: 75 percent of the food burned is converted to heat and 25 percent is converted to useful work. How long will the student have to ride to lose one pound by conversion of mass to energy? How come you do not have to exercise this long to lose a pound?

1 Mass and Energy Use the equivalence of energy and rest mass, E = mc² to answer the following questions. (a) The total electrical energy generated in the United States is on the order of 10¹2 kWh per year. How much mass is this equivalent to? (b) The earth's orbital radius is about 1.5 × 10¹1 m. At this distance from the sun, the energy flux of sunlight is about 1.4 kW/m². How much mass does the sun radiate as light in one second? (c) A student pedaling a bicycle full throttle produces about one-half horsepower of useful power. (1 hp is equivalent to 746 W.) The human body is about 25 percent efficient: 75 percent of the food burned is converted to heat and 25 percent is converted to useful work. How long will the student have to ride to lose one pound by conversion of mass to energy? How come you do not have to exercise this long to lose a pound?

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter5: Relativity

Section: Chapter Questions

Problem 113AP: The sun energy at a rate of 3.85×10 26 W by the fusion of hydrogen. About 0.7% of each kilogram of...

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