Here's why:
* Inertia: Inertia is an object's resistance to changes in motion. The more massive an object is, the harder it is to get it moving or to stop it once it's moving.
* Matter: Matter is anything that occupies space and has mass. It's composed of atoms and molecules, which have inherent properties like mass.
Therefore, the amount of matter in an object directly corresponds to its resistance to changes in motion. This is why mass is considered the measure of how much matter an object contains.
Key points:
* Mass is an intrinsic property: It's an inherent characteristic of an object, not dependent on its location or environment.
* Weight is not mass: Weight is the force of gravity acting on an object's mass. It can vary depending on location (e.g., on the moon vs. on Earth).
In essence, mass quantifies the fundamental resistance of an object to changes in motion, which directly stems from the amount of matter composing it.
