The quantity that is not conserved in an inelastic collision is

$A$ particle falls from a height $h$ on a static horizontal plane and rebounds. If $e$ is the coefficient of restitution,then the total distance traveled by the particle before coming to rest will be:

$A$ ball is moving with speed $20 \, m/s$ collides with a smooth surface as shown in the figure. The magnitude of the change in velocity of the ball will be ........... $m/s$.

$A$ sphere of mass $m$ moving with velocity $u$ collides with another sphere of the same mass $m$ at rest. If the coefficient of restitution is $e = \frac{1}{2}$, what is the ratio of their velocities after the collision?

$A$ ball of mass $1.2 \ kg$ moving with a velocity of $12 \ ms^{-1}$ makes a one-dimensional collision with another stationary ball of mass $1.2 \ kg$. If the coefficient of restitution is $\frac{1}{\sqrt{2}}$,then the ratio of the total kinetic energy of the balls after the collision to the initial kinetic energy is:

An object of mass $m$ moving with velocity $u$ collides with another stationary object of mass $M$ and stops just after the collision. The coefficient of restitution is