In an inelastic collision,after collision the kinetic energy

$A$ ball is dropped from a height $h$. After it strikes the ground twice,what height will it reach?

$A$ ball moving with a velocity of $6\, m/s$ strikes an identical stationary ball. After collision,each ball moves at an angle of $30^{\circ}$ with the original line of motion. What are the speeds of the balls after the collision?

$A$ ball strikes a horizontal surface as shown in the figure. If the coefficient of restitution is $e = 1/\sqrt{3}$,then the angle $\theta$ is ............... $^o$.

$A$ particle falls from a height $h$ upon a fixed horizontal plane and rebounds. If $e$ is the coefficient of restitution,the total distance travelled before rebounding has stopped is

$A$ ball makes a head-on collision with another ball of twice its mass,which is initially at rest,with a velocity of $1.5 \ m/s$. If the coefficient of restitution is $0.6$,what will be their velocities after the collision?