How does an increase in mass affect an object's inertia?

Inertia is the property of matter that describes an object's resistance to changes in its state of motion. The greater the mass of an object, the greater its inertia. This relationship is grounded in Newton's first law of motion, which asserts that an object at rest will stay at rest and an object in motion will continue in motion with the same speed and in the same direction unless acted upon by an external force.

As an object's mass increases, it becomes harder to change its velocity, whether starting from rest or altering its current state of motion. Therefore, when mass is increased, inertia correspondingly increases, meaning it would require a greater force to accelerate the object. This principle is fundamental in mechanics and illustrates why heavier objects are more challenging to move or stop compared to lighter ones.

The assertion that inertia remains the same or that mass does not affect inertia does not align with physical laws. It's crucial to understand that inertia is directly proportional to mass; therefore, as mass increases, so does inertia.