An automobile vehicle has a mass of $1500 \, kg$. What must be the force (in $N$) between the vehicle and road if the vehicle is to be stopped with a negative acceleration of $1.7 \, m \, s^{-2}$?

$A$ motorcar of mass $1200\, kg$ is moving along a straight line with a uniform velocity of $90\, km/h$. Its velocity is slowed down to $18\, km/h$ in $4\, s$ by an unbalanced external force. Calculate the acceleration and change in momentum. Also,calculate the magnitude of the force required.

$A$ hockey ball of mass $200 \,g$ travelling at $10 \,m \,s^{-1}$ is struck by a hockey stick so as to return it along its original path with a velocity of $5 \,m \,s^{-1}$. Calculate the magnitude of the change in momentum of the hockey ball due to the force applied by the hockey stick.

Two objects,each of mass $1.5\, kg$,are moving in the same straight line but in opposite directions. The velocity of each object is $2.5\, m/s$ before the collision during which they stick together. What will be the velocity (in $m/s$) of the combined object after collision?

Which of the following has more inertia: $(a)$ a rubber ball and a stone of the same size? $(b)$ a bicycle and a train? $(c)$ a five-rupee coin and a one-rupee coin?

In the following example, try to identify the number of times the velocity of the ball changes:
"$A$ football player kicks a football to another player of his team who kicks the football towards the goal. The goalkeeper of the opposite team collects the football and kicks it towards a player of his own team".
Also identify the agent supplying the force in each case.