Trajectory of a Tennis Serve
Trajectory of a Tennis Serve
Professional tennis players often hit serves at 200 km/hr or even faster. In order to guarantee that a serve will land within the designated service box, players must apply torque on the ball so that the ball will "spin" into the court due to the additional force that the angular velocity creates. This additional force is created because as the ball spins, it disrupts airflow, so that the air on different sides of the ball is moving at different speeds. As a consequence, the pressure on the opposite sides of the ball is also different, by Bernoulli’s principle. Because of this pressure difference, a net force acts on the ball, thus causing it to curve downward. This Demonstration represents a 3D plot of the trajectory of a serve, showing how it is affected by the spin on the ball. The server is standing on the right-hand side of the court.