A 68-kg commuter rides on an 8.1 -kg bicycle. Each bicycle wheel is a hoop of radius 33 cm and mass 1 A kg. (a) What energy must the biker supply to move at 7.2 m/s? include the kinetic energy of the biker, the kinetic energy of the bike frame, and the kinetic energy of the rotating wheels. (b) What percentage of the energy she expends goes into the rotation of the wheels? (c) What percentage goes into her own kinetic energy?
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