$A$ body of mass $M$ collides against a wall with a velocity $v$ and retraces its path with the same speed. The change in momentum is (take initial direction of velocity as positive).

$A$ particle of mass $m \, kg$ moving with a velocity $v \, m/s$ strikes a surface as shown in the figure and rebounds with the same speed. The magnitude of the change in momentum is:

$A$ ball of mass $50 \,g$ is dropped from a height of $20 \,m$. $A$ boy on the ground hits the ball vertically upwards with a bat with an average force of $200 \,N$,so that it attains a vertical height of $45 \,m$. The time for which the ball remains in contact with the bat is ........... of a second. [Take $g = 10 \,m/s^2$]

$A$ force is applied to a body of mass $2 \,kg$ at rest on a frictionless horizontal surface, as shown in the force-time $(F-t)$ graph. The speed of the body after $1 \,s$ is: (in $\,m/s$)

$A$ machine gun fires a bullet of mass $65 \, g$ with a velocity of $1300 \, m/s$. The man holding it can exert a maximum force of $169 \, N$ on the gun. The number of bullets he can fire per second will be ............

Explain "Momentum gives more information than velocity alone".