A neutron makes a head-on elastic collision with a stationary deuteron. The fractional energy loss of the neutron in the collision is

A ball of $0.4\,kg$ mass and a speed of $3\, m/s$ has a head-on, completely elastic  collision with a $0.6-kg$ mass initially at rest. Find the speeds of both balls after the  collision:

A billiard ball moving with a speed of $5 \,m/s$ collides with an identical ball originally at rest. If the first ball stops after collision, then the second ball will move forward with a speed of ...........  $m{s^{ - 1}}$

$A$ ball is thrown vertically downwards with velocity $\sqrt {2gh} $ from $a$ height $h$. After colliding with the ground it just reaches the starting point. Coefficient of restitution is

A ball $P$  collides with another identical ball  $Q$  at rest. For what value of coefficient of restitution $e$ , the  velocity of ball  $Q$  become two times that of ball  $P$  after collision

A body is dropped on ground from a height $h_1$ and after hitting the ground, it rebounds to a height $h _2$ If the ratio of velocities of the body just before and after hitting ground is $4$, then percentage loss in kinetic energy of the body is $\frac{x}{4}$. The value of $x$ is $.......$