## SECTION B - Circular Motion
1976M1. A small block of mass m slides on a horizontal frictionless surface as it travels around the inside of a hoop of radius R . The coefficient of friction between the block and the wall is μ; therefore, the speed v of the block decreases. In terms of m,R.μ, and v , find expressions for each of the following.
a. The frictional force on the block
b. The block's tangential acceleration dv/dt
c. The time required to reduce the speed of the block from an initial value v0 to v0/3