No, all bodies do not have the same inertia. Inertia depends on the mass of the object; the greater the mass, the greater the inertia.

Inertia and mass are closely related, with mass serving as a measure of an object’s inertia. The greater the mass of an object, the greater its inertia, and therefore its resistance to changes in motion or rest.

The quantitative measure of inertia in an object is its mass. Mass indicates the amount of matter in an object and is directly related to its inertia.

We determine the relative inertia of objects by comparing their tendencies to resist changes in their states of motion. In the example given, the train exhibits more inertia compared to the cart because it requires more force to change its ...

A force that can cause a small cart to pick up a large velocity produces only a negligible change in the motion of a train because the train has much more mass and therefore more inertia compared to the cart. ...