Question

Inertia of a body depends on:
A. Mass of the body
B. Velocity of the body
C. Acceleration of the body
D. Energy of the body

Answer 1

Hint: Inertia of a body is its nature to resist any change in its current state of rest or uniform motion. Heavy objects are difficult to move than the lighter objects because they have more inertia than the lighter objects.

Complete step by step answer:
Inertia of a body is the tendency of that body to resist any change. Every particle or body in the universe has the nature to be its state whether it is at rest or in uniform motion. The body does want any change in its motion or it does want to move from its state of rest. It will not change its state on its own. That is why an unbalanced force is needed to be applied on the body to change its state i.e. to accelerate (to change the velocity of the body) it. When a force is applied on a body, how it will accelerate depends on the mass of the body. More the mass less is the value of the acceleration of the body, when the same amount of force is applied. Suppose there are two bodies of different masses. Same force is applied on both the bodies. The body of larger mass that will have less acceleration than the other body. That is how mass provides nature to resist the change in its state i.e. the inertia of the body. For example, it is very difficult to move a heavy boulder (large mass) because its mass is very large and thus the inertia is more. Whereas it is very easy to move a lighter stone because it has very less mass and thus less inertia. Therefore, it cannot resist to that extent and moves very easily.
Hence, the mass of the body on which the inertia of the body depends. The correct option is (a) mass of the body.

Note: Sometimes students misunderstand that mass and the inertia of a body are the same. However, they are not the same but related to each other. As discussed, inertia is the nature of the body to resist the change in its state and mass is the amount of matter in the body. Inertia of the body depends on the mass of the body.