$A$ string is wrapped around a cylinder of radius $r$ and moment of inertia $I$. $A$ mass $m$ is attached to one end of the string. The cylinder can rotate freely about its horizontal axis. If the mass $m$ is released from rest at a height $h$,what will be its velocity?

Between the hour hand of a clock and the rotation of the Earth about its own axis,which has a lower angular speed?

Two small balls are fixed at the ends of a light rigid rod of length $L = 0.4 \ m$. The system is released from a height $h = 5 \ m$ with the rod horizontal. The balls collide with the horizontal surface and rebound. The coefficient of restitution between ball $A$ and the ground is $e_A = 0.6$ and that between ball $B$ and the ground is $e_B = 0.4$. Find the angular speed (in $rad/s$) of the rod just after the collision. Take the acceleration due to gravity $g = 10 \ m/s^2$.

What is a rigid body?

The moment of inertia of a solid flywheel about its axis is $0.1\,kg\cdot m^2$. $A$ tangential force of $2\,kg\cdot wt$ is applied around the circumference of the flywheel with the help of a string and mass arrangement as shown in the figure. If the radius of the wheel is $0.1\,m$,find the angular acceleration of the solid flywheel (in $rad/s^2$). (Take $g = 9.8\,m/s^2$)

$A$ ball of mass $m$ is released from inside a smooth wedge of mass $m$ as shown in the figure. What is the speed of the wedge when the ball reaches point $B$?