$A$ block having mass $m$ collides with another stationary block having mass $2m$. The lighter block comes to rest after the collision. If the initial velocity of the first block is $v$,then the value of the coefficient of restitution must be:

In the elastic collision of objects,

$A$ heavy body moving with a velocity of $6\,ms^{-1}$ collides elastically with a light body (whose mass is half of the mass of the heavy body) at rest. The velocity of the light body will be (in $ms^{-1}$):

Which of the following potential energy curves in the figure cannot possibly describe the elastic collision of two billiard balls? Here $r$ is the distance between the centres of the balls.

$A$ smooth sphere $A$ is moving on a frictionless horizontal plane with an angular velocity $\omega$ and its center of mass is moving with a linear velocity $v$. It undergoes an elastic collision with a stationary sphere $B$. (Ignore friction everywhere). If the angular speeds after the collision are $\omega_A$ and $\omega_B$ respectively,then:

Two identical spheres move in opposite directions with speeds $v_1$ and $v_2$ and pass behind an opaque screen,where they may either cross without touching (Event $1$) or make an elastic head-on collision (Event $2$).