The first golf balls in 1550 were made out of wood until they were replaced by cow hide spheres stuffed with goose feathers. Dimples on golf balls were not added until 1905 when they took their modern form. Golf balls have between 300 and 500 dimples with an average depth of about 0.010 inch (0.0254 cm). But why were they added on the first place?
The reason is obvious: scuffed-up balls travel farther than smooth balls. This is happening because the dimples create turbulence that, if done right, reduces drag.
Here’s how it works. (the article continues after the ad)
There are two main types of airflow – laminar and turbulent. If the ball is smooth, the air flow around the ball is laminar which means that air is quickly separated from the ball. This creates a vortex and a swirling of the air, which creates heavy drag. On the other hand, dimples create turbulence in layers of air around the ball. Turbulence sucks air to the ball so the separation is delayed which results in smaller vortex and less drag. Because of the reduced drag, the ball can travel farther:
But how much farther can a dimple golf ball reach?
According to Tom Veilleux, a senior scientist, and Vince Simonds, director of aerodynamic research at the Top-Flite Golf Company, a ball with dimples would travel twice as far as a smooth golf ball does.