The use of aerodynamic forces by the expert golfer was demonstrated to me once by a drive off the tee by a well-known professional, Arnold Palmer. I stood directly behind him so that I could have the best view of the flight of the ball. Instead of the ball going on the parabolic path I had expected, it climbed in a nearly straight line for about 3 seconds and then began to fall. Recall that Newton’s first law states that a body continues in a straight line at constant speed unless a force acts on it. The nearly straight path indicated an almost zero net force acting on the ball in the vertical direction. Where did this lifting force about equal to the weight of the ball come from? It was the aerodynamic force on the dimpled spinning ball, traveling at a high speed, that was balancing the vertical force of gravity.
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