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How does Newton’s third law explain the forces between a tennis racket and a tennis ball?

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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, for every action, there is an equal and opposite reaction. When a tennis racket strikes a tennis ball, the racket exerts a force on the ball, causing a sudden change in the ball's motion. Simultaneously, the ball exerts a force back on the racket that is equal in magnitude and opposite in direction to the force applied by the racket.1

These two forces constitute an action-reaction pair, with each force acting on a different body—one on the ball and the other on the racket. This interaction explains why a player feels the shock of the impact when the racket hits the ball. Furthermore, a second set of balanced action and reaction forces occurs between the player and the racket, completing the physical interaction of the system.21