BALLS

If we ignore the effect of air, the movement of the centre of mass is the same for all objects and all athletes: it is a parabola. But many sports rely on the effect of air which dominates over gravity when objects are light, moving fast or spinning quickly. Without air, there would be no slice in golf or cut balls in table tennis. These lifting, curving and slowing forces are complicated. We will analyze mainly the slowing force on a fast object (which depends on the shape, texture and velocity) and the curving force on a rotating object, which can bend the trajectory to the left or right, or up or down.