A sphere collides with another sphere of identical mass. After collision, the two spheres move. The collision is inelastic. Then the angle between the directions of the two spheres is

Explain the special cases of elastic collision in one dimension.

A sphere strikes a wall and rebounds with coefficient of restitution $1/3$. If it rebounds with a velocity of $0.1\, m/sec$ at an angle of $60^o$ to the normal to the wall, the loss of kinetic energy is

In $a$ one-dimensional collision, $a$ particle of mass $2m$ collides with $a$ particle of mass $m$ at rest. If the particles stick together after the collision, what fraction of the initial kinetic energy is lost in the collision?

$A$ chain of length $L$ and mass $m$ is placed upon a smooth surface. The length of $BA$ is $L-b$. Calculate the velocity of the chain when its end reaches $B$.

A ball is dropped from height $5\,\,m$. The time after which ball stops rebounding if coefficient of restitution between ball and ground $e = 1/2$, is ............. $\mathrm{sec}$