In a carom-board game the striker and the coins are identical and of mass $m$ . In a particular hit the coin is hit when it is placed close to the edge of the board as shown in figure such that the coin travels  parallel to the edge. If the striker is moving with speed $v$ before the strike, then the net impulse on the striker during collision if it moves perpendicular to the edge after collision, is (assume all collisions to be perfectly elastic)

A body of mass $5 \,kg$ is moving with velocity of $\vec{v}=(2 i+6 \hat{j}) \,m / s$ at $t=0 \,s$. After time $t =2 \,s$, velocity of body is $(10 \hat{i}+6 \hat{j})$, then change in momentum of body is ......... $kg m / s$

The mass of a hydrogen molecule is $3.32 \times 10^{-27 } $ $kg$. If $10^{23}$ hydrogen molecules strike, per second, a fixed wall of area $2$ $cm^2$ at an angle of $45^o $ to the normal, and rebound elastically with a speed of $10^3\ m/s$, then the pressure on the wall is nearly:

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

The motion of a particle of mass $m$ is described by $y=u t+\frac{1}{2} g t^{2} .$ Find the force acting on the particle.

In an hour-glass approximately $100$ grains of sand fall per second (starting from rest); and it takes $2 \, s$ for each sand particle to reach the bottom of the hour-glass. If the average mass of each sand particle is $0.2 \,g$, then the average force exerted by the falling sand on the bottom of the hour-glass is close to .......... $N$