A uniform disc of mass m and radius R is projected horizontally with velocity `v_(0)` on a rough horizontal floor so that it starts with a purely sliding motion at t= 0. After `t_(0)` seconds it acquires a purely rolling motion.
(a) Calculate the velocity of the centre of mass of the disc at `t_(0)`
(b) Assuming the coefficient of friction to be `mu`, calculate to. Also calculate the work done by the frictional force as a function of time and the total work done by it over a time t muchlonger than `t_(0)`.
