A massless string is wrapped around a uniform solid cylinder of mass 30 kg and radius 0.20 m. One end of the string is attached to the cylinder and the free end is pulled tangentially by a force that maintains a constant tension of 3.0 N. Find (a) the angular acceleration and (b) the angular speed of th cylinder 2.0 s after the force is applied to the cylinder at rest.

A massless string is wrapped around a uniform solid cylinder of mass 3

1.	A massless string is wrapped around a uniform solid cylinder of mass 30 kg and radius 0.20 m. One end of the string is attached to the cylinder and the free end is pulled tangentially by a force that maintains a constant tension of 3.0 N. Find (a) the angular acceleration and (b) the angular speed of th cylinder 2.0 s after the force is applied to the cylinder at rest.
Answer» Solution :(a) We KNOW that `TAU = I ALPHA` `F.r = I alpha F.r =(mr^(2))/(2).rArr alpha = (2F)/(mr)=(2XX3)/(30xx0.2)=1 rad//s^(2)` (b)`omega_(2)-omega_(1)=alpha t therefore omega_(2)=alpha t` angular speed after 2 sec, `omega_(2)=1xx2=2` rad/sec.