Dimples in Golf Balls Reduce Air Resistance

Q: Why do golf balls have dimples?

A: Their purpose is to reduce air resistance, and thus help the balls fly longer distances.

A well-hit golf ball leaves the tee at a speed of about 120 mph.

At that speed, a spinning ball with a smooth surface has a thick layer of air around it, called a boundary layer. That air, in effect, makes the ball bigger, increasing resistance and slowing the ball.

The dimples increase turbulence in the boundary layer, reducing its size and making the ball travel faster and farther.