Mass is a measure of what property of an object?

Mass is a measure of an object's inertia, which is the resistance of an object to any change in its state of motion. This means that a more massive object requires more force to change its velocity compared to a less massive object. Inertia is fundamentally tied to mass; the greater the mass, the greater the inertia, making it more difficult to start moving or to stop.

In contrast, weight is the force exerted by gravity on an object, which is dependent on both mass and the acceleration due to gravity. Energy and volume are related to an object’s physical properties but do not directly describe mass. Understanding mass in terms of inertia helps explain the behavior of objects in motion and is a foundational concept in physics.