The tennis ball is made from synthetic materials and about ten different chemicals. The sheets covering the ball are made from these materials, and they are cut into strips shaped like the number 8. Two strips are then heated up to a certain temperature inside a pressure chamber, and the edges of the strips are joined using a latex-like adhesive. The natural atmospheric pressure on Earth is 14.7 pounds per square inch, while the air pressure inside the ball is kept at 13 pounds per square inch to give it a harder feel whenever it is squeezed. If the internal pressure of the ball is the same as the external pressure outside, then the ball’s pitching on the tennis court would not absorb the force of its momentum. The ball would bounce higher than the racket, which is extended above the head of the opposite player because the equal air pressure inside and also outside the ball would not allow the object to compress as it hits the ground of the court. However, the small difference of 1.7 pounds per square inch between the internal and external pressure is not sufficient to keep the bounce low. The low bounce of the ball is the reason why a coat of furry felt made out of nylon, wool, and Dacron fibers are pasted on top of the ball to give it more bounce.
As the tennis ball pitches or hits on the ground, the felt covering it is compressed first, and then it is followed by the compression of the synthetic material beneath the felt. Both the phenomena ultimately absorb much more force of impact. One of the important laws of tennis indicates that the ball launched from the height of 100 inches above the court should not bounce on the ground higher than 58 inches. The said law is meant to ensure that the bounce of the ball is controlled in order for the opponent to hit it on the other side. Another important purpose of applying the furry felt on the tennis ball is for the reduction of its speed through friction with the air so that it will be given some more time (even if it is a fraction of a second) for the player to return a fiery service or even to hit a volley. One more advantage of the felt covering is that its fibrous surface prevents the ball from slipping on the catgut cord, which is a part of the racket, even if it is hit from a slanting angle. On the other hand, playing with a fiber-less and smooth ball tends to receive negative from players, who find it difficult to judge where the ball will pitch since it travels faster, and its directions often change when it hits the ground.
Who invented the tennis ball?
The first tennis balls with a furry coating were invented in the late 11th century, although the sport of tennis was created in the early years of the same century. The first furry tennis balls were made of leather, and they are wrapped with either fur or wool. Sadly, there are no historical records saying who invented the furry tennis balls, but it is believed that it was someone from the nobility who came up with the materials for the ball.
The leather-based tennis balls would go on to be the primary ball of choice for tennis players until the 19th century. However, because the balls are made out of luxury materials, most people can’t afford to buy it, hence the reason why tennis only became accessible for those who belong to the higher class.
Thankfully, the prices for tennis balls dropped when an alternative material was utilized to replace the leather inner, and this material is rubber. The first rubber tennis balls were created by Charles Goodyear, who most car enthusiasts would probably be familiar with to be the pioneer in rubber tires for certain vehicles. These rubber tennis balls were invented during the 1870s when industrialization and the manufacturing of rubber became prominent in western countries. The synthetic tennis balls were first used for lawn tennis, which is played on non-grass surfaces, but it was eventually utilized as the standard ball for tennis.