Magnus Effect – The effect on a spinning cylinder or sphere moving through a fluid, in which force acts perpendicular to the direction of motion and to the direction of spin. This is used to advantage in baseball, in which the trajectory of a pitched ball is a distinct curve. Applied to aeronautics in experimental wingforms, the Magnus Theory states that if air is directed against a smooth, revolving cylinder, whose circumferential speed is greater than that of the air current, a force is directed against one side of the cylinder—air compressed on one side and vacuum formed on the other—creating lift. Named for physicist Heinrich Gustav Magnus.
