A 4878-kg car is driving down a portion of highway that is inclined 10° with respect to the horizontal and 100 m long. When it reaches the bottom of the incline, its kinetic energy has increased by 730 kJ and 400 kJ have been lost to air resistance. a) How much work has been done by the force of gravity? b) Using the work-kinetic energy theorem, how much work must have been done by the car’s engine?

A 4878-kg car is driving down a portion of highway that is inclined 10° with respect to the horizontal and 100 m long. When it reaches the bottom of the incline, its kinetic energy has increased by 730 kJ and 400 kJ have been lost to air resistance. a) How much work has been done by the force of gravity? b) Using the work-kinetic energy theorem, how much work must have been done by the car’s engine?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter9: Energy In Nonisolated Systems

Section: Chapter Questions

Problem 17PQ

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