M
Mass
In physics, mass is an intrinsic positive physical quantity of a body, which measures its resistance to acceleration. In modern physics, it is generally defined as the strength of an object's gravitational attraction to other bodies — as measured by an observer moving along at the same speed. The unit of mass in the International System of Units (SI) is the kilogram (kg). Mass was traditionally thought to be related to the amount of matter contained in a physical body, until the emergence of ele
