Two balls each of mass $250 \ g$ moving in opposite directions each with a speed $16 \ m \ s^{-1}$ collide and rebound with the same speeds. The impulse imparted to one ball due to the other is

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 .......... $N$.

Explain why the product of mass and velocity is important in producing the effect of force.

$A$ body of mass $5 \, kg$ is moving with a momentum of $10 \, kg \cdot m/s$. $A$ force of $0.2 \, N$ acts on it in the direction of motion of the body for $10 \, seconds$. The increase in its kinetic energy is ............... $J$.

What physical quantity is represented by the area under the force-time graph?

$A$ bullet of mass $20 \,g$ moving with a velocity of $200 \,m/s$ strikes a target and is brought to rest in $\left(\frac{1}{50}\right) \,s$. The impulse and average force of impact are respectively: