The momentum $p$ of an object varies with time $(t)$ as shown in the figure. The corresponding force $(F)$-time $(t)$ graph is

$1000$ small balls,each weighing $1 \text{ g}$,strike $1 \text{ cm}^2$ of area per second with a velocity of $50 \text{ m/s}$ in a normal direction and rebound with the same velocity. The value of pressure on the surface will be:

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

The time in which a force of $2 \, N$ produces a change of momentum of $0.4 \, kg \cdot m/s$ in a body is ......... $s$.

$A$ solid horizontal surface is covered with a thin layer of oil. $A$ rectangular block of mass $m = 0.4 \ kg$ is at rest on this surface. An impulse of $1.0 \ N \ s$ is applied to the block at time $t = 0$ so that it starts moving along the $x$-axis with a velocity $v(t) = v_0 e^{-t/\tau}$,where $v_0$ is a constant and $\tau = 4 \ s$. The displacement of the block,in metres,at $t = \tau$ is. . . . . . . Take $e^{-1} = 0.37$.

$A$ $140\,g$ ball,in horizontal flight with a speed of $39.0\,m/s$,is struck by a bat. After leaving the bat,the ball travels in the opposite direction with a speed of $39.0\,m/s$. If the impact time $\Delta t$ for the ball-bat collision is $1.20\,ms$,calculate the average force in $N$ acting on the ball.