A hoop of radius 3.05 m has a mass of 145 kg. Its moment of inertia is mR². The hoop rolls without slipping along a horizontal plane. If the center of mass of the hoop has a speed of 0.305 m/s, the work required to bring the hoop to rest is A) 6.78 J. B) 13.5 J. C) 682 J. D) 217 J. E) 4.34 kJ.

Question

Quizplus · Accepted Answer

The total kinetic energy of the hoop is the sum of translational and rotational kinetic energy. The work required to bring the hoop to rest is equal to this total kinetic energy. Calculating it gives 13.5 J.

A Hoop of Radius 3