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Why do golf balls have pits? Why do golf balls have pits

If we count patiently, we will find that there are more than 300 holes in the golf ball. The average depth of each hole is about 0.025 cm. In fact, there are many holes on the surface of golf balls, which is the result of dynamic aerodynamics. The existence of these holes is precisely to reduce air resistance, and increase the lift of the ball, so that the golf ball can fly further.

The trajectory of the ball is not only affected by its own gravity, but also by the resistance of the incoming air. Therefore, how to reduce air resistance becomes the key. When the golfer hits the ball, each ball gets a kind of backward rotation force, which is closely related to these dents, like forming a thick air cushion under the ball. A golf ball will fly at high speed after being hit, and there will be a high pressure area in front of it. When air flows through the front edge of the ball and then to the rear, it separates from the ball. At the same time, the air behind the ball will form a turbulent wake, which affects the size of the resistance. The cavity on the ball can reduce the change of airflow direction, make the airflow behind more smooth, thus reducing the range of wake. This reduces drag by about 20%. In addition, in the course of the ball's rotation, a ball with a cavity will obtain nearly twice the lift force by deflecting the airflow.

The cavity reduces the drag in flight and provides additional lift, thus providing better aerodynamic performance. The ball can then fly farther, higher and more accurate. In addition, the golf rules also stipulate that the shape of the golf ball cannot be changed at will.

Today's standard golf balls have different brands, but they all adopt the surface dent type. If it is a golf ball with smooth surface, the flying distance is far less than the ball with groove on the surface after being hit by professional players. Some people have tried, playing smooth ball can only fly 65 meters away, and the ball with dent can hit 275 meters.