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How can two objects exert equal and opposite forces while moving differently?

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Title page of Isaac Newton's Philosophiae Naturalis Principia Mathematica, 1687, featuring large Latin text and publication details in a bordered layout. — Newton’s laws of motion The title page of Isaac Newton's *Philosophiae Naturalis Principia Mathematica* (1687; *Mathematical Principles of Natural Philosophy*), the work in which the physicist introduced his three laws of motion.

According to Newton’s third law of motion, when two bodies interact, they exert forces on each other that are equal in magnitude and opposite in direction. These forces are an action-reaction pair, but it is critical to understand that they always act on different bodies.12

Because each force acts on a separate object, the resulting motion of each object depends on the net force acting upon it, as described by Newton’s second law. An object’s acceleration is determined by the sum of all forces acting on that specific body, not just the single force involved in the third-law interaction.13

For example, if you push a heavy object, you exert a force on it, and it exerts an equal and opposite force on you. While these forces are equal, your respective motions differ because your masses are different and other external forces (such as friction or gravity) may be acting on each of you independently. The third law applies regardless of whether the bodies are at rest, in uniform motion, or accelerating.41