# This Is Why Golf Balls Have Dimples

Updated: Oct. 04, 2021

The dimples on a golf ball serve a greater purpose than just making it look cute—no ifs, ands, or putts.

There’s just so much to learn when it comes to the world we live in. Like, what are those colored squares on toothpaste? What are the solo cup lines actually for? What do the numbers on a toaster really mean? Why do golf balls have dimples? Whether you’re a golf pro or only began wondering why golf balls have dimples after checking out this piece, we’re here to break down the game of golf into simple physics. Don’t worry, it’s not as daunting as you may think.

## Why do golf balls have dimples?

The first golf balls were actually smooth. But as golfers began to play more and more, they noticed that older balls with bumps, scratches, and gashes actually seemed to travel farther.

Scientists soon learned why this is: it all has to do with something called a turbulent wake region. When a ball is traveling through the air, the air flows over the front side of the ball and towards the back where it will eventually separate as the ball continues to soar. The turbulent wake region is the area behind the ball that has been disturbed as the ball passes through the air. Makes sense, right? Stay with us.

Dimples create a thin boundary layer of the air that adheres to the ball’s surface. This allows the air to stay on the ball’s surface a little longer as it moves around the back side of the ball. This decreases the ball’s drag. (Drag is the force that takes place as a result of a change in velocity, opposing the motion and slowing it down.)

The dimples on a golf ball also affect its lift. If the ball was smooth, the ball would get lift from its backspin. This makes the air pressure on the bottom of the ball larger than the air pressure on the top, creating an upward force. The spin contributes to about half of the ball’s lift, while the other half is produced by the dimples which optimize the lift so the ball can go even higher.

Therefore, the game of golf that we know today wouldn’t be possible without the dimples. Keep the learning going and find out what the indent on a wine bottle really means.

## What happens if a golf ball has no dimples?

Logically it seems like a small ball would travel farther and faster than those with dimples, but that is scientifically not the case. Picture a smooth golf ball sailing through the air. The sun is out. The birds are chirping. There is an ideal amount of wind. As the ball moves, the front will come into contact with the air.

The air that hits the front of the ball will smoothly go over the ball and separate from the ball at the back. That separation will create a turbulent wake region that results in low pressure, making the ball drag. So much drag, in fact, that a smooth golf ball would only travel half as far as a dimpled golf ball.

## How many dimples are on a golf ball?

The typical golf ball has between 300 and 500 dimples on average with an average depth of approximately .010 of an inch. The dimples are usually spherical, but other shapes (like hexagons) have been used in experiments to optimize performance. The lift and drag on a golf ball are extremely sensitive to depth. According to Scientific American, if the depth changes a mere .001 of an inch, this can radically change the golf ball’s trajectory and potential distance it can go. Now that you know why golf balls have dimples, learn what those colored circles on food packages actually mean.

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