Most golf balls have between 300 and 500 dimples covering the surface of the ball, which have an average depth of about 0.010 inch.

A smooth golf ball hit by a professional golfer would travel only about half as far as a golf ball with dimples does. The lift and drag forces on a golf ball are very sensitive to dimple depth: a depth change of 0.001 inch can produce a radical change to the ball's trajectory and the overall distance it can fly.

Dimples have traditionally been spherical in shape, but it is possible to optimize the aerodynamic performance of other shapes.

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