Match the items in Column-$I$ with Column-$II$.

Column-$I$	Column-$II$
$(1)$ Work done is zero	$(a)$ By gravitational force (when body moves down)
$(2)$ Work done is positive	$(b)$ Against gravitational force (when body moves up)
$(3)$ Work done is negative	$(c)$ By centripetal force

$A$ tennis ball is dropped on a horizontal smooth surface. It bounces back to its original position after hitting the surface. The force on the ball during the collision is proportional to the length of compression of the ball. Which one of the following sketches describes the variation of its kinetic energy $K$ with time $t$ most appropriately? The figures are only illustrative and not to the scale.

Two spheres $A$ and $B$ of masses $m_1$ and $m_2$ respectively collide. Sphere $A$ is at rest initially and sphere $B$ is moving with velocity $v$ along the $x$-axis. After the collision,sphere $B$ has a velocity of $\frac{v}{2}$ in a direction perpendicular to the original direction. The mass $A$ moves after the collision in the direction:

$A$ ball of mass $1 \ kg$ moving with a velocity of $0.4 \ m/s$ collides with another ball of the same mass at rest. After the collision,the first ball moves with a velocity of $0.3 \ m/s$ in a direction perpendicular to the initial direction. Find the magnitude of the momentum $\vec{P}$ of the second ball in $kg \cdot m/s$.

$A$ ball falls freely from rest on to a hard horizontal floor and repeatedly bounces. If the velocity of the ball just before the first bounce is $7 \text{ m/s}$ and the coefficient of restitution is $0.75$. The total distance travelled by the ball before it comes to rest is (acceleration due to gravity $= 10 \text{ m/s}^2$) (in $\text{ m}$)

$A$ sphere of mass $m$ travelling at constant speed $v$ strikes another sphere of the same mass. If the coefficient of restitution is $e$,then the ratio of the velocities of both spheres just after the collision is: