What is the angular velocity of the second hand of a clock?

$A$ body moves along a circular path of radius $15 \ cm$. It starts from a point on the circular path and reaches the end of the diameter in $3 \ s$. The angular speed of the body in $rad/s$ is

$A$ particle is moving in a circle of radius $r$ with center at $O$,with a constant speed $v$. The magnitude of the change in velocity when moving from point $A$ to point $B$ is

The figure shows a small wheel fixed coaxially on a bigger one of double the radius. The system rotates about the common axis. The strings supporting $A$ and $B$ do not slip on the wheels. If $x$ and $y$ are the distances travelled by $A$ and $B$ in the same time interval,then

Two particles having mass $M$ and $m$ are moving in circular paths having radii $R$ and $r$. If their time periods are the same,then the ratio of their angular velocities will be:

$A$ particle is moving with a constant speed $v$ in a circle. What is the magnitude of average velocity after half rotation?