Do you know why squash balls need to be warm? If you drop a cold squash ball, it won't bounce much. But when it gets warm, it bounces a lot more. This is because squash balls are made of special rubber. Rubber is different from other things. When it gets warm, it gets smaller, not bigger. This helps it bounce more.
There are two reasons why warm squash balls bounce more. First, the rubber in the ball gets smaller when it's warm. This makes the molecules inside the ball get closer together. When the molecules are close, the ball bounces more. Second, when the ball gets warm, the air inside the ball gets hotter and wants to get out. This makes the ball bounce even more.
Squash players know this, so they warm up the ball before they play. They hit the ball hard to make it warm, or they rub it with their shoe to make it warm faster. This helps them play better.
