The property of an object because of which it resists to get disturbed its state is called inertia. The inertia of an object is measured by its mass. Inertia is directly proportional to the mass. This means inertia increases with increase in mass and decreases with a decrease in mass. A heavy object will have more inertia than the lighter one.
In other words, the natural tendency of an object that resists the change in state of motion or rest of the object is called inertia.
Since a heavy object has more inertia, thus it is difficult to push or pull a heavy box over the ground than the lighter one.
