Have you ever been hit hard with a squash ball on the head? Well, I have. A squash ball is generally made up of raw rubber, consisting of various different synthetic and natural chemicals and materials. A lot of different types of squash balls are manufactured, depending upon the play styles of the players. However, the material of a squash ball can be generalized as extraordinarily bouncy and airy from inside. In case you are into sports, you must be aware that all professional squash players spend at least an hour or two warming up.
The main purpose of this extended warm-up period is to get the ball nice and warmed up. The players try to hit the ball as hard as possible during this warm-up period. Because, more the amount of force applied on the squash ball by the rackets, more is the heat energy generated on the surface of the ball, which is ultimately transferred to the air inside the squash ball. The air inside the ball will now possess a certain amount of thermal energy, which finally gets converted into kinetic energy of molecules, and the air particles inside the squash ball get activated. The word “activated” refers to the motion of the molecules towards the edges of the ball. The flowchart below will help you understand the phenomenon better-
So, now we know, what happens during the warm-up period in squash. Let’s jump straight forward into the interesting part. Do you remember the hot air concept which you might have studied during Grade7 or 8? Well, that concept isn’t as useless as it seemed to be when you studied it. We know that hot air tends to rise up and expand. The same phenomenon happens inside the ball. This phenomenon results in the ball becoming hard from the outside. Ultimately, the rubber of the ball becomes even more bouncy and flexible. So, despite the soft physical nature of rubber, the rubber itself becomes really tight and compact from the outside.
Now, the question arises, what exactly is the use of applying so much brain into just making a squash ball? Well, a rubber squash ball has both the opposing physical properties- Flexibility, and compactness, only by the virtue of the concept which we just understood. But, apart from that, rubber squash balls have another huge advantage.
Rubber squash balls can be customized according to the nature of the ball required. What I mean by the word “nature of the ball” is that differently skilled players can play with different types of squash balls. For e.g. the professional squash players often play with the super slow squash ball which makes the game even more intense and nail-biting for the audience. But, a beginner cannot play with that type of squash ball. For, beginners, there is a different type of squash ball, which enables them to learn and adapt to the game more easily. The most interesting thing here is that even with the exact same amount of force applied, the super slow ball will travel a lot less distance, as compared to the beginners' squash ball. Carefully observe the graph below-
In the above graph, the applied force is constant despite the variation in the trajectory of the ball.
So, the next time you visit a squash court, or go and play squash, you will know exactly, what phenomenon is occurring inside the squash ball? Doesn’t that seem awesome? Continue reading the rest of the posts on PHYSICS EVERDAY.