Kicking a football requires less force than kicking a basketball. Why?

There are three solids made up of aluminium,steel,and wood,of the same shape and same volume. Which of them would have the highest inertia?

Define $1\, kg$ weight and express it in newton.

$A$ block is supported by a cord $A$ from a rigid support,and another cord $B$ is attached to the bottom of the block. If you give a sudden jerk to $B$,it will break. But if you pull on $B$ steadily,$A$ will break. Why?

The velocity-time graph of a ball of mass $20 \ g$ moving along a straight line on a level ground is given below. How much force does the ground exert on the ball to bring it to rest?

What type of force is acting in the cases given above?