Tennis Balls

by Sarah
(Winston Salem, NC)

Typical bounce for a tennis ball

Figuring things out is a quiet joy - Often, the best discoveries don't come from big claims or loud debates, but from paying attention. The world becomes a lot more interesting when you trust your own senses and ask honest questions.

The science project that I remember most was about tennis balls. My question was whether tennis balls bounce higher when they are hot or cold. I don't even remember why I thought of that, but it turned out to be really interesting.

I ended up making a measuring guide out of this big sheet. I then heated up some of the tennis balls and put some in the freezer to cool down. I draped the sheet over a balcony (I happened to live in an apartment complex) and dropped the balls from the second story.

My dad was down below with a camera. He tried to capture the balls bouncing as they hit the ground. My conclusion was that it didn't really matter, but there was something else interesting that happened.

For some reason, none of the shots of the tennis balls developed. My dad is pretty professional when it comes to pictures, but for some reason they didn't turn out. He couldn't figure out why.

My teacher told me to mention this in my science project, and I did. It turns out that the judges were pretty interesting in this information. I ended up getting an honorable mention. I guess it just goes to show that even when you think you've messed the experiment up, you can write about it and turn it around!

Barry's Response - The best scientific discoveries were made by accident. What one perceives as a failure can turn out to be the greatest success they ever had...all by accident. Thanks for your story, Sarah.

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Balls for tennis

What makes a tennis ball bounce? It's full of air that pushes back.

Warm air spreads out and pushes harder. Cool air slows down and pushes less. That's just physics. That's also meteorology. The same idea explains why warm air rises, storms grow, and winds blow.

Sarah tested it by heating some tennis balls and freezing others. So the test stayed fair, she dropped them from the same height. That's important. It's called "controlling variables," but kids call it "not cheating."

There wasn't much change in bounce height. Real science happens all the time. Nature shrugs and says, "Not today."

But then something else happened. Photos didn't work. Sarah wrote it down instead of hiding it. Science values honesty more than polish, so that choice impressed the judges.

Sensors break in weather science. Balloons pop and satellites miss stuff. Scientists don't lie. It's written down and they ask why.

Here's where it gets fun and defiant

Some people think science always speaks loudly. No, it doesn't. Science argues with itself. Models are questioned and we check assumptions. In climate and air quality work, data gets rechecked, methods get better and ideas get better. No, that's not denial. It's what makes you strong.

Tennis balls have gas laws inside. The air in the atmosphere does too. Whether you like it or not, pressure, temperature, and volume dance together. That helps farmers, pilots, engineers, and yes, people who measure air pollution.

Reasonable people see this order as design. From a skeptical perspective, it's just physics at work. You can run the same experiment in the same room.

Do you want to try this at home?

Chalk a wall to measure bounce height. Test sunny vs. shady days. Compare old and new balls. Find out why the differences appear or disappear.

It's science. Not loud. Not perfect. I'm just honest and curious.

What would you test next with tennis balls? Let us know what surprised you in the comments.

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Thank you to my research and writing assistants, ChatGPT and WordTune, as well as Wombo and others for the images.

OpenAI's large-scale language generation model (and others provided by Google and Meta), helped generate this text.  As soon as draft language is generated, the author reviews, edits, and revises it to their own liking and is responsible for the content.