$A$ ball is dropped from a height of $10 \ m$ and hits the roof of an elevator moving downwards with a velocity of $1 \ m/s$. What is the rebound velocity of the ball in $m/s$?

$A$ block of mass $m$ slides with speed $v$ on a frictionless table towards another stationary block of mass $m$. $A$ massless spring with spring constant $k$ is attached to the second block as shown in the figure. The maximum distance the spring gets compressed is

Particle $A$ makes a perfectly elastic collision with another particle $B$ at rest. They fly apart in opposite directions with equal speeds. If their masses are $m_A$ and $m_B$ respectively,then:

$A$ body of mass $8 \ kg$ undergoes an elastic collision with a stationary body of mass $2 \ kg$. If the initial kinetic energy is $E$,then the kinetic energy remaining with the $8 \ kg$ body after the collision is ............ $E$.

Explain the special cases of elastic collision in one dimension.

As per the given figure,a small ball $P$ slides down the quadrant of a circle and hits another ball $Q$ of equal mass which is initially at rest. Neglecting the effect of friction and assuming the collision to be elastic,the velocity of ball $Q$ after the collision will be $............\,m/s$ $(g = 10\,m/s^2)$.