What is the force required to accelerate a $2 \, kg$ mass by $5 \, m s^{-2}$ (in $, N$)?

$A$ man pushes a box of mass $50\, kg$ with a force of $80\, N$. What will be the acceleration of the box due to this force? What would be the acceleration if the mass were doubled?

When a missile is fired from a tank,it gets a momentum of $2000 \ kg \ m \ s^{-1}$. If the velocity of the missile is $50 \ m \ s^{-1}$,what will be its mass (in $kg$)?

In a high jump athletic event,the athletes are made to fall on a cushioned bed. Why?

Show that the rate of change of momentum $=$ mass $\times$ acceleration.

$A$ man weighing $60 \, kg$ runs along the rails with a velocity of $18 \, km \, h^{-1}$ and jumps into a car of mass $1 \, \text{quintal} \, (100 \, kg)$ standing on the rails. Calculate the velocity with which the car will start travelling along the rails.