Dimples
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Hi, this is Dave Thurlow for The Weather Notebook. Today we're going to explore the physics of golf balls. They soar through the air with the greatest of ease -- except when I hit 'em.

A golf ball's surface design is what helps them travel so far. Once a ball is struck, it falls under the influence of two forces trying to slow it down. One is gravity and the other is friction between the ball and the air, also known as wind resistance.

After the upward force of the club smacking the ball weakens, gravity takes hold and the ball descends. You can't do much about gravity, but you can do something about wind resistance. A golf ball is covered with dimples. Why? Because a smooth ball has a tiny layer of air molecules that clings to its surface. This layer acts somewhat like a coating of jelly and it slows the ball down. It increases the wind resistance. Put dimples all over the surface and the jelly like layer blows away in flight.

The dimples cause turbulence, little swishes of air that knock clinging air molecules away. This allows the golf ball to be exposed to the air rushing by. The ball is slipperier, the wind resistance decreases, and the ball zings along, all because of the dimples.

Now I wonder why they don't put dimples on cars. Any thoughts? Let us know. Call 1-888-RAIN-001 or visit our website at weathernotebook.org. The Weather Notebook is a production of the Mount Washington Observatory. And, is underwritten by Subaru: The beauty of all-wheel drive.