1. The problem statement, all variables and given/known data A tangential force F acts at the top of a thin spherical shell of mass m and radius R. Find the acceleration of the shell if it rolls without slipping. 2. Relevant equations Since the shell is rolling, friction does not act at the bottom. So equating the torque, F*R= I*α 3. The attempt at a solution So putting in value of Moment of inertia for a hollow sphere, I=2/3mR^2 and α=a(COM)/R And solving for a, i got a=3F/2m But the correct answer is : 6F/5m Where am i going wrong?