The moment of inertia of a wheel about its vertical axis is $2 \ kg \ m^2$. It is rotating about this axis at a speed of $60 \ rpm$. What torque must be applied to bring the wheel to rest in $1 \ minute$?

Moment of inertia of a body about an axis is $4 \,kg-m^2$. The body is initially at rest and a torque of $8 \,N-m$ starts acting on it along the same axis. Work done by the torque in $20 \,s$,in joules,is

$A$ constant torque acting on a uniform circular wheel changes its angular momentum from $A_0$ to $4 A_0$ in $4$ seconds. The magnitude of this torque is ...........

$A$ uniform rod of mass $M$ and length $L$ is hinged at one end as shown in the figure. Initially,the rod is kept horizontal by a massless string. When the string is cut,the angular acceleration of the rod is:

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