Question

Two balls of same size one of rubber and second of iron are placed on floor which one has more inertia

Answer 1

The iron ball has more inertia .
This is because , inertia depends upon the mass of the object, greater the mass , greater would be the inertia.

Answer 2

Inertia is the natural tendency of an object to resist the change in state of rest or motion. So as mass increases , inertia possessed by an object also increases. As Iron ball has more mass compared to rubber ball. Hence it has more inertia.