The gravitational force is directed downwards and is equal to F G = m g, Trajectory of a ball bouncing at an angle of 70° after impact without drag, with Stokes drag, and with Newton drag.
The bounciness of balls has been a feature of sports as ancient as the Mesoamerican ballgame. To ensure fair play, many sports governing bodies set limits on the bounciness of their ball and forbid tampering with the ball's aerodynamic properties. The motion of a ball is generally described by projectile motion (which can be affected by gravity, drag, the Magnus effect, and buoyancy), while its impact is usually characterized through the coefficient of restitution (which can be affected by the nature of the ball, the nature of the impacting surface, the impact velocity, rotation, and local conditions such as temperature and pressure). However, the exact modelling of the behaviour is complex and of interest in sports engineering. Several aspects of a bouncing ball's behaviour serve as an introduction to mechanics in high school or undergraduate level physics courses.
The physics of a bouncing ball concerns the physical behaviour of bouncing balls, particularly its motion before, during, and after impact against the surface of another body.
The motion is not quite parabolic due to air resistance.
