$A$ block of mass $2 \ kg$ is free to move along the $x$-axis. It is at rest and from $t=0$ onwards it is subjected to a time-dependent force $F(t)$ in the $x$ direction. The force $F(t)$ varies with $t$ as shown in the figure. The kinetic energy of the block after $4.5 \ s$ is (in $J$)

$A$ large number $(n)$ of identical beads,each of mass $m$ and radius $r$,are strung on a thin smooth rigid horizontal rod of length $L$ $(L >> r)$ and are at rest at random positions. The rod is mounted between two rigid supports. If one of the beads is now given a speed $v$,the average force experienced by each support after a long time is (assume all collisions are elastic):

$A$ particle is acted upon by a force whose components' variations with time are shown in the diagrams. The magnitude of the change in momentum of the particle in $0.1\,s$ is:

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.

Two bodies $A$ and $B$ collide as shown in Fig. $(i)$ and $(ii)$. Which statement is true?

$A$ cricket ball of mass $250\, g$ collides with a bat with velocity $10\, m/s$ and returns with the same velocity within $0.01\, s$. The force exerted on the ball is ....... $N$.