A particle of mass m is released from rest on the horizontal rim of a fixed hemispherical
bowl of radius r and slides downward under gravity.
a. Draw the FBD of the particle at some position in the bowl, and assuming a
friction coefficient y, find the differential equation for 0, the angle of the
particle's position below the rim, measured from the center;
b. Solve the differential equation to obtain l as a function of e