Q. In a truck-loading station at a post office, a small package is released from rest at point on a track that is one quarter of a circle with radius (figure). The size of the package is much less than , so the package can be treated as a particle. It slides down the track and reaches point with a speed of . From point , it slides on a level surface a distance of to point , where it comes to rest.

What is the coefficient of kinetic friction on the horizontal surface?

Work, Energy and Power Report Error

Solution:

The magnitude of the work done by friction is the kinetic energy of the package at point ,
or ,
or