Two identical billiard balls undergo an oblique elastic collision. Initially, one of the balls is stationary. If the initially stationary ball after collision moves in a direction which makes an angle of $37°$ with direction of initial motion of the moving ball, then the angle through which initially moving ball will be deflected is

A ball of mass $\mathrm{m}$ collides horizontally with a stationary wedge on a rough horizontal surface, in the two orientations as shown. Neglect friction between the ball and the wedge. The students comment on the system of ball and wedge in these situations

Saurav: Momentum of the system in $x$ -direction will change by significant amount in both the cases. Rahul: There are no impulsive external forces in $x$ -direction in both cases, hence the total momentum of the system in $x$ -direction can be treated as conserved in both cases.

A $20 \mathrm{g}$ bullet pierces through a plate of $mass{M}_1=1 \mathrm{kg}$ and then comes to rest inside a second plate of mass $M_2=2.98 \mathrm{kg}$ as shown in figure. It is found that the two plates, initially at rest, now move with equal velocities. Find the percentage loss in the initial velocity of the bullet when it is between $M_1$ and $M_2.$ Neglect any loss of material of the plates due to the action of bullet.

A ball released from a height $h_0$ above a horizontal surface rebounds to a height $h_1$ after one bounce. The graph that relates $h_0$ to $h_1$ is shown in figure. If the ball (of the mass $\mathrm{m}$ ) was dropped from an initial height $h$ and made three bounces, the kinetic energy of the ball immediately after the third impact with the surface was

Two identical balls of equal masses $A$ and $B$ , are lying on a smooth surface as shown in the figure. Ball $A$ hits the ball $B$ (which is at rest) with a velocity $v=16\mathrm{ }\mathrm{m} {\mathrm{s}}^{-1}$ . What should be the minimum value of coefficient of restitution $e$ebetween $A$ and $B$ so that $B$ just reaches the highest point of inclined plane. $\left(g=10\mathrm{ }\mathrm{m} {\mathrm{s}}^{-2}\right)$