Systems of Particles and Rotational motion

A cord of negligible mass is
wound round the rim of a fly wheel of mass
20 kg and radius 20 cm. A steady pull of
25 N is applied on the cord as shown in
Fig. 6.31. The flywheel is mounted on a
horizontal axle with frictionless bearings.
(a) Compute the angular acceleration of
the wheel.
(b) Find the work done by the pull, when
2m of the cord is unwound.
(c) Find also the kinetic energy of the
wheel at this point. Assume that the
wheel starts from rest.
(d) Compare answers to parts (b) and (c).