A ball of mass $m$ is moving with a speed $V$ as shown in the figure. It undergoes inelastic collision with a ball of mass $2\ m$ which was initially at rest. The velocity of ball $2\ m$ after collision will be given by

In the above question, if another body is at rest, then velocity of the compound body after collision is

A body falls on a surface of coefficient of restitution $0.6 $ from a height of $1 \,m$. Then the body rebounds to a height of ...........  $m$

A point mass of $1 \mathrm{~kg}$ collides elastically with a stationary point mass of $5 \mathrm{~kg}$. After their collision, the $1 \mathrm{~kg}$ mass reverses its direction and moves with a speed of $2 \mathrm{~ms}^{-1}$. Which of the following statement(s) is (are) correct for the system of these two masses?

$(A)$ Total momentum of the system is $3 \mathrm{~kg} \mathrm{~ms}^{-1}$

$(B)$ Momentum of $5 \mathrm{~kg}$ mass after collision is $4 \mathrm{~kg} \mathrm{~ms}^{-1}$

$(C)$ Kinetic energy of the centre of mass is $0.75 \mathrm{~J}$

$(D)$ Total kinetic energy of the system is $4 \mathrm{~J}$

Aball of mass $m$ collides elastically with an identical ball at rest with some impact parameter.

A mass $m_1$ moves with a great velocity. It strikes another mass $m _2$ at rest in a head on collision. It comes back along its path with low speed, after collision. Then