Tennis & golf balls

Figure 1 shows a common tennis ball. The required size and weight for official tennis balls is 2.575 to 2.700 inches and 1.975 to 2.095 ounces. Tennis balls are filled with air and are surfaced by a uniform felt-covered rubber compound. Tennis balls are tested by dropping from a height of 100 inches into concrete at 68F; a bounce between 53 and 58 inches is deemed acceptable.

Figure 1: Standard Tennis Ball

Figure 2 illustrates a common golf ball. The required size and weight for official golf balls is no less than 1.680 inches and no more than 1.620 ounces. Modern multi-layer balls are made from various synthetic materials like surlyn or urethane blends. The dimples on the surface of the golf ball cause the boundary layer on the ball to transition from laminar to turbulent, which remains attached to the surface of the ball much longer, creating a lower pressure wake and thus less pressure drag.

Figure 2: Standard Golf Ball