Name the factor on which the inertia of a body depends.

When a net force acts on an object,the object will be accelerated in the direction of the force with an acceleration proportional to:

$A$ 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.

What are the changes possible on an object at rest if we apply on it:
$(a)$ a balanced force?
$(b)$ an unbalanced force?

State the reason for the following:
$(i)$ Some leaves may get detached from a tree if we vigorously shake its branch.
$(ii)$ It is advised to tie any luggage kept on the roof of a bus with a rope.

The inertia of an object tends to cause the object