The Pitch   Have you ever wondered whether a curve ball really curves, or is it just an optical illusion? Now with the current technology, like fast photography, we can show that a curve ball really does curve. Physicists began to wonder what made the baseball actually curve, and in research the found that a force called the magnus force is actually what cause the baseball to curve. It is just like when a plane is flying and the air on top of the wing is less than the air on the bottom of the more which pushes the plane up. Well when a baseball is spinning, the spinning baseball will cause there to be more pressure on one side then the other causing the baseball to curve.   http://library.thinkquest.org/11902/physics/curve2.html The amount that a curve ball will curve can be determined by the equation: FMagnus Force = KwVCv Where FMagnus Force is the Magnus Force, K is the Magnus Coefficient, w is the spin frequency measured in rpm, V is the velocity of the ball in mph, Cv is the drag coefficient.