A block of mass m=kg is hanging from a rope attached to a pulley.
The pulley has a mass M=kg and a radius of R=m.
The block is held fixed, then suddenly released.

What is the angular acceleration of the pulley?

How long after being released will the block be falling at a speed of v=m/s?
(The moment of inertia of the pulley is I=^{1}/_{2} MR^{2}.)