An object slides down a smooth incline and reaches the bottom with velocity $v$. If same mass is in the form of a ring and it rolls down an inclined plane of same height and angle of inclination, then its velocity at the bottom of inclined plane will be ............

If the angular velocity of a merry-go-round is $60^o/sec$ and you are $3.5\,m$ from the centre of rotation, your linear velocity will be

In an experiment with a beam balance an unknown mass $m$ is balanced by two known masses of $16\,kg$ and $4 \,kg$ as shown in figure. The value of the unknown mass $m$ is ......... $kg.$

Three thin rods each of length $L$ and mass $M$ are placed along $x, y$ and $z-$ axes is such a way that one end of each of the rods is at the origin. The moment of inertia of this system about $z-$ axis is 

A child is standing at one end of a long trolley moving with a speed $v$ on a smooth horizontal floor. If the child starts running towards the other end of the trolley with a speed $u$, the centre of mass of the system (trolley + child) will move with a speed.

One end of a rod of length $L=1 \,m$ is fixed to a point on the circumference of a wheel of radius $R=1 / \sqrt{3} \,m$. The other end is sliding freely along a straight channel passing through the centre $O$ of the wheel as shown in the figure below. The wheel is rotating with a constant angular velocity $\omega$ about $O$. The speed of the sliding end $P$, when $\theta=60^{\circ}$ is