It’s the one piece of equipment we use on every shot, yet most don’t give it a whole lot of thought. Golf balls seem so simple, but have you ever wondered how they actually work? Now, before we get into the science of flight, let’s take a quick peek into the history of golf balls. After all, you have to understand where you’ve been to appreciate where you’re going.
A long time ago, in a golf galaxy far, far away (no, not the one just down the street) golf balls looked a lot different. One of the game’s earliest models was called a “Featherie.” Its design was fairly simple: goose feathers tightly packed into a hand-sewn horse- or cow-hide. Though highly functional for 1618 (not to mention expensive, sometimes costing more than the actual clubs that hit them) featheries didn’t fly too far.Fast forward nearly 300 years to 1905 when William Taylor gave the game a lift – quite literally – when he applied an innovative dimple patter to his golf ball. The results were massive gains in distance and accuracy. But why? Why does a simple indentation in the surface of the golf ball make such a huge difference?
Grab a pen and paper; it’s time for Physics of Golf 101.
After impact (which lasts for 1/2000 of a second), the only forces acting on a golf ball are gravity and aerodynamics, no matter how much you “kindly” persuade it not to take a dip in the lake. Air exerts a force on any object moving through it; that force is broken down in two parts: lift and drag.
Drag
During flight, your golf ball has a high-pressure area on its front side. Air flows smoothly over the contours of the front and separates when it comes around to the back. Moving objects also leave behind a turbulent wake which results in lower pressure behind it. The size of that wake affects the amount of drag on an object. Here’s where the dimples come in; they create a thin turbulent boundary layer of air that clings to the ball’s surface and decreases the size of its wake. A smaller wake results in less drag and more “boom, boom” for your buck.
Dimples also affect lift. As well all know golf balls create backspin (sometimes a little too much backspin). A spinning motion creates lift by warping airflow around the object resulting in an imbalance of pressure (higher amounts on the bottom) creating upward forces on the ball. While spin accounts for a portion of that lift, dimples do the rest of the work by allowing for the optimization of the lift force.
Think of it this way: if the core of a golf ball is the engine, the dimples are its wings.
But here’s the funniest part of the story: dimples actually came about by happenstance. Back in the day golfers noticed that the more scuffed up their golf ball, the farther and straighter it flew. The original dimples were nothing more than scrapes and scuffs, so don’t let a blemish or two stop you from using a golf ball. In fact, it may actually help you!
Image Source: http://www.nj.com/golf/index.ssf/2009/06/michael_guillenthe_starledgert.html