$A$ horizontal heavy uniform bar of weight $W$ is supported at its ends by two men. At the instant one of the men lets go of his end of the rod,the force on the other man's hand changes to:

What is the physical quantity of the time rate of the angular momentum?

Consider a $20\, kg$ uniform circular disk of radius $0.2\, m$. It is pin supported at its center and is at rest initially. The disk is acted upon by a constant force $F = 20\, N$ through a massless string wrapped around its periphery as shown in the figure. Suppose the disk makes $n$ number of revolutions to attain an angular speed of $50\, rad/s$. The value of $n$,to the nearest integer,is.......... [Given: In one complete revolution,the disk rotates by $6.28\, rad$]

What constant force must be applied tangentially at the equator to stop the Earth's rotation in one day?

$A$ uniform disc rotates at $10$ revolutions per second. $A$ torque is applied to it, producing an angular acceleration of $5 \text{ rad s}^{-2}$. After $2 \text{ s}$, its angular velocity is ...... $\text{rad s}^{-1}$ and the number of revolutions completed by the disc in $2 \text{ s}$ is ...... .

$A$ slender uniform rod of mass $M$ and length $l$ is pivoted at one end so that it can rotate in a vertical plane (see figure). There is negligible friction at the pivot. The rod is released from a position where it makes an angle $\theta$ with the vertical. The angular acceleration of the rod when it makes an angle $\theta$ with the vertical is