$A$ batsman hits back a ball of mass $0.4 \; kg$ straight in the direction of the bowler without changing its initial speed of $15 \; ms^{-1}$. The impulse imparted to the ball is $\dots \; Ns$.

State whether the following statements are true or false:
$(a)$ The product of the mass of an object and its velocity is called linear momentum.
$(b)$ Inertia is mass,and the measure of inertia is the resistance to change.
$(c)$ Force is the change in momentum.

$A$ $2 \ kg$ object is initially at rest. It is acted upon by a force as indicated in the figure. Find the total work done by the force in $3 \ s$. (in $J$)

Two billiard balls each of mass $0.05\; kg$ moving in opposite directions with speed $6\; m/s$ collide and rebound with the same speed. What is the impulse imparted to each ball due to the other (in $; Ns$)?

Which force acts on a body first: action or reaction?

An athlete runs for some distance before taking a long jump. Why?