What does Newton's Second Law of Motion describe?

Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. This relationship can be succinctly expressed with the equation force equals mass times acceleration (F = ma). This principle clarifies how the motion of an object changes when a force is applied, specifying that larger forces result in greater accelerations, and that heavier objects require more force to achieve the same acceleration as lighter ones.

This law is fundamental to understanding dynamics, as it provides a clear mathematical framework for predicting how objects will move when forces are applied. Rather than addressing action-reaction pairs, momentum conservation, or states of motion individually, this law precisely encapsulates the relationship between force, mass, and acceleration, making it a cornerstone of classical mechanics.