Confusing results for squash balls bounce

[greener1993]

Hey guys, how are you? :D

I’m doing an experiment on a squash ball where I drop it from a 0.5m height and work out its "bounced height" to determine energy lose with the table. By per=mgh

When dropping it from 0.5 m I get a result of 0.125m on the first bounce. However when I tried it with a hole placed in the squash ball the bounce was higher at 0.135m this pattern continued for all bounces and all tests.

The reason it is confusing me is because I believed that when the ball hit the table it became deformed into an oval shape the pressure inside the ball increases and "pushes" the ball back into the original shape, whist doing so giving it height on the return.

However with a hole I expected this pressurised gas to leave the ball and wouldn't push the ball back into its original shape as quickly or with the same magnitude.

The results have taken me by surprise and would be grateful if someone could explain the physics is hide this increase in height to me.

 

[LightHero]

Hi there! We're doing great, thanks for asking! It sounds like you have an interesting experiment going. We can't give a definitive answer without being able to run the experiment ourselves, but we can offer some possible explanations. When the ball is punctured, the air escapes and creates a vacuum in the ball. This vacuum could potentially increase the elasticity of the ball, leading to a higher bounce. Alternatively, the decrease in air pressure in the ball could lead to a lower drag force, which could also contribute to a higher bounce. Additionally, when the ball is punctured, the shape of the ball changes slightly, which could also increase the bounce. Hope this helps!