The Swing, Part 4
Physics also explains why the same swing can produce different results. The heads of the longer clubs will be traveling at higher speeds because they are farther away from center of the radius of the swing arc. No additional effort is necessary on the golfer's part to produce this higher swing speed. This additional club-head speed will produce additional distance.
The faces of the clubs have different lofts. The lofts on the clubfaces cause the balls to rise and the dimples cause them to spin, which also causes them to rise. This loft, combined with a shorter club, controls the distance. You make the same swing, and yet your ball does something totally different with an 8 iron than it does with a 3 wood.
Physics also explains why we hit balls that hook and slice. When you cut across the ball-target line with your swing path you put side spin on the ball, which makes the ball either hook or slice.
Physics provides us the answer to an age-old problem, the out-to-in swing path. You can avoid this problem from the start if you understand the swing and how it works. The arc of the arm pendulum is controlled by your left arm from the top of the backswing through contact with the ball, with the right arm acting as a stabilizer. To deliver maximum swing speed and repeatability the ideal swing path is in-to-out-to-in. This means that the swing arc travels through the hitting zone. More than 90 percent of golfers swing through the hitting zone with a swing arc.
To keep this combined pendulum on an in-to-out-to-in path you must transfer your weight to your front foot before you begin the downswing. The consequences for not making this weight transfer will be an out-to-in swing path.
The critical time during the downswing for the wrist pendulum is about waist-high when your shoulders are still 30-40 degrees turned away from the ball-target line. If you have not rotated sufficiently on the backswing to achieve this position (on the backswing we must rotate a full 90 degrees to the rear with our shoulders), or if your wrists do not begin to uncock at this time, the club head will move outside and cross the ball target line from out-to-in, causing a slice or a pull. This uncocking happens naturally in the golf swing. If you force it, or incorrectly begin your swing with your hands (also known as "hitting over the top" or casting ) you will not drop your right shoulder and arm, and you will throw the head of the club outside of the arm pendulum or plane from the beginning of the swing.