Two spheres are rolling with same velocity (for their $C. M.$) their ratio of kinetic energy is $2 : 1$ & radius ratio is $2 : 1$, their mass ratio will be :
$2 : 1$
$4 : 1$
$8 : 1$
$2\,\sqrt 2 :1$
A wheel of radius $20\, cm$ has forces applied to it as shown in the figure. The net torque produced by the forces $4\, N$ at $A, 8\, N$ at $B, 6\, N$ at $C$ and $9\, N$ at $D$ at angles indicated is
Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are $v$ and $2v$ at any instant, then the speed of centre of mass of the system will be
A particle of mass $m$ moves along line $PC$ with velocity $v$ as shown.What is the angular momentum of the particle about $O$ ?
A ball is thrown on a lawn in such a way that it initially slides with a speed $v_0$ without rolling. It gradually picks up rotation motion. Find the speed of the ball at which there will be rolling without slipping-
What is the torque of force $\vec F = 2\hat i - 3\hat j + 4\hat k$ acting at a point $\vec r = 3\hat i + 2\hat j + 3\hat k$ about the origin?