$100$ balls each of mass $m$ moving with speed $v$ simultaneously strike a wall normally and reflect back with the same speed in time $t \ s$. The total magnitude of force exerted by the balls on the wall is

$A$ machine gun fires $20$ bullets per second into a target. Each bullet weighs $150 \, g$ and has a speed of $800 \, m/s$. Find the force necessary to hold the gun in position.

$A$ player caught a cricket ball of mass $150 \ g$ moving at a speed of $20 \ m/s$. If the catching process is completed in $0.1 \ s$,the magnitude of the force exerted by the ball on the hand of the player is .......... $N$.

In the figure shown,a balloon is pressed against a wall. It is in equilibrium and maximum compressed state. $\vec F_1 =$ force of balloon on hand of man; $\vec F_2 =$ force of balloon on wall; $\vec F_3 =$ friction; $\vec F_4 =$ weight of balloon. Choose the correct statement.

$A$ bullet of mass $10\,g$ leaves the barrel of a gun with a velocity of $600\,m/s$. If the barrel of the gun is $50\,cm$ long and the mass of the gun is $3\,kg$,then the value of the impulse supplied to the gun will be $.....\,Ns$.

The figure shows the position-time $(x-t)$ graph of one-dimensional motion of a body of mass $0.4 \; kg$. The magnitude of each impulse is: