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?

Using a horizontal force of $200\, N$,we intend to move a wooden cabinet across a floor at a constant velocity. What is the friction force (in $N$) that will be exerted on the cabinet?

Two objects of masses $100 \, g$ and $200 \, g$ are moving along the same line and direction with velocities of $2 \, m \, s^{-1}$ and $1 \, m \, s^{-1}$,respectively. They collide and after the collision,the first object moves at a velocity of $1.67 \, m \, s^{-1}$. Determine the velocity (in $m/s$) of the second object.

According to the third law of motion,when we push on an object,the object pushes back on us with an equal and opposite force. If the object is a massive truck parked along the roadside,it will probably not move. $A$ student justifies this by answering that the two opposite and equal forces cancel each other. Comment on this logic and explain why the truck does not move.

Akhtar, Kiran, and Rahul were riding in a motorcar that was moving with a high velocity on an expressway when an insect hit the windshield and got stuck on the windscreen. Kiran suggested that the insect suffered a greater change in momentum compared to the motorcar. Akhtar said that since the motorcar was moving with a larger velocity, it exerted a larger force on the insect. Rahul said that both the motorcar and the insect experienced the same force and the same change in momentum. Comment on these suggestions.

$A$ 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.