Two particles having mass 'M' and 'm' are moving in a circular path with radius 'R' and 'r' respectively. The time period for both the particles is same. The ratio of angular velocity of the first particle to that of the second particle will be

Which of the following person is in an inertial frame of reference?

The spring is initially in unstretched condition. It is first stretched by a length '$x$' and the work done is $W_1$. Then again it is stretched by further length '$x$' when the work done is $W_2$. The value of $W_2$ is given by

A thin uniform rod AB of mass '$m$' and length '$l$' is hinged at one end A to the ground level. Initially the rod stands vertically and is allowed to fall freely to the ground in the vertical plane. The angular velocity of the rod when its B end strikes the ground is
($g$ = acceleration due to gravity)