Ask The Science Experts

The principle factor affecting a moving (and spinning) baseball is air drag. Imagine a standard fastball thrown with a straight overhead motion. The ball will be spinning naturally on a horizontal axis (with the top of the ball rotating back toward the pitcher). This spin causes the magnitude of the drag vectors to be different [...]

The dimples reduce drag allowing the ball to travel faster for a longer time- and thus farther. The dimples reduce drag because the fast-moving air tends to remain closer to the dimpled surface than it would on a smooth surface. Basically this reduces the eddies and the wake effect.