M

In physics, "M" typically represents mass, which is the amount of matter in an object. It is a fundamental property that determines how much an object weighs and how it responds to forces like gravity. Mass is different from weight; weight depends on gravity, while mass remains constant regardless of location. Understanding "M" helps explain phenomena such as inertia (resistance to change in motion) and the behavior of objects under various forces. In essence, mass is a measure of an object's "stuff" or material content, providing a foundational concept in physics and mechanics.