The tennis player It approaches the background line, receives 3 or 4 balls from the gruesome – i Ball Boys and Girls – he observes them, the key, he bounces them and discarded one or two and prepares for the service. If you came across a tennis match, maybe Wimbledon in these days, you will have happened to attend this scene, but why do they do it? What differences can there be between two practically identical tennis balls? Well, the reasons and differences are manifold, It is not about scaramma But it contains concepts of physics, aerodynamics And psychology. The selection depends on wear, on the presence of hair on the surface and internal pressure of the ball, all characteristics that affect the strategy of the service itself by changing the rebound and trajectory.
During a tennis match of ATP tournaments and of the four Grand Slams6 new balls are changed each 9 gameexcept at the beginning that the balls are also used for heating and are replaced after the first 7 game. In this period of time they are subjected to physical and mechanical stress being affected several times with high power. These tensions modify the anatomy of the ball by using them differently and modifying the trajectories. The hair (Fuzz In English) on the surface it is a fundamental feature for this concept as it not only allows you to make the blows much more controllable, but also to increase the grip of the racket on the ball. This is precisely what the player or player assesses during the selection precedes the service:
- New ball: a less used ball has less hair on the surface, opposes less air resistancetherefore traveling faster. This ball will be chosen and used for the before servicewhen the tennis player can use the maximum power to look for a ace (winning service) and put the opponent in difficulty.
- Wear ball: A more hairy ball has a more rough surface, occupies more volume and creates greater friction with the air making the blow slower. This feature proves useful when the athlete must carry out the second serviceafter making the first wrong. In this case we try to create problems for your rival, not through maximum power but having the check of the service and giving a effect to the ball thanks to a greater grip on the rifting ropes, also having a higher error margin.
In addition to being a physical question, the choice of the ball proves to be a psychological ritual for many tennis players. The gesture of choosing carefully the ball represents a break for re -enter and find the maximum concentrationreset the mind After an error And break the opponent’s rhythm. In short, in tennis nothing is left to chance and the obsessive attention for every detail can make the difference between a good service and an unformed error or between a victory and a defeat.
