A cotton reel of mass `m`, radius `R` and moment of inertia `I` is kept on a smooth horizontal surface. If the string is pulled horizontally by a force `F`, find the (i) acceleration of `CM`, (ii) angular acceleration of the cotton reel.

Explanation

a. The net force acting on the cotton reel is
`F=ma_(C)`

or `a_(C)=F/m`
b. the net torque about the CM is `tau_(C)(=FR)=Ialpha`
(as torques produced by mg and `N` about `C` are zero as they pass through the `CM`).
Then `alpha=(FR)/I`