S4 Tennis

Title

Tennis integrates hitting (M5) with the racket as an implement, movement on the court (M2/M7), service (M5+M4) and return (M5+E8). The serve is the fastest technical gesture: the ball can exceed 220 km/h in elite tennis players. The kinetic chain in the serve goes from the opening of the foot to the racket-ball impact: hip rotation trunk shoulder elbow wrist racket. The speed of the racket head (~50 m/s on serve) directly determines the exit speed of the ball. The Magnus effect (topspin/backspin) controls the trajectory and bounce of the ball: topspin makes the ball fall faster and bounce higher. The stiffness of the racket and the point of impact with respect to the vibration node (sweet spot) determine the efficiency of energy transfer and the player's comfort (reduction of impact shock). Friction between string and ball generates the spin necessary for topspin.

ID:2362