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© Copyright 1998, Jim Loy
A Super Ball is a hard rubber ball, which has a rough surface, and bounces very efficiently. When they first came out, a friend of mine told me that one bounces higher than it was when you dropped it. I didn't believe him, and I continued to disbelieve all those years, until now.
A Super Ball does bounce much higher than you expect (if you haven't seen one before). And it is natural to be so impressed that you THINK that it bounced higher than it was when you dropped it. It is an optical illusion, based on your expectations of how high it will bounce. The ball bounces almost as high as you held it, and you say "Wow." A similar optical illusion is the rising fastball, in baseball. A normal fastball seems to fly almost horizontally, when it is actually dropping a lot, an illusion. The rising fast ball does not fall nearly as much, and it seems to be rising. But, the rising fast ball is actually falling, just not as much as you expect it to. This illusion is well-documented. Just watch a slow-motion movie of the pitch, and you will see that the rising fastball drops. A rising line drive (or a rising golf drive) does rise.
The laws of physics say that the Super Ball cannot gain energy, without some outside source of energy. A basketball can bounce up and down, almost forever, and even bounce higher and higher, because there is a basketball player dribbling it. He/she is the outside source of energy.
While doing research for an article on bank shots, in pool. I came upon the article Racquetball by Jearl Walker, in Roundabout, a collection of articles from Scientific American. In this article we see a ball, make a low bounce with spin, followed by a high bounce with little spin, followed by a low bounce... I had been seeing Super Balls do this, for all those years. And I didn't really see it. Of course the spin energy is the source of energy for the higher bounce. We are just seeing conversion of energy from one form to another, which is the main message of physics, actually.
So, your Super Ball can bounce higher than when you drop it, if you spin it right.
I assume that Super Ball is someone's trademark, or something like that. I called the local toy store, and the lady responded, "You mean Bouncy Balls?" Bouncy Balls? Give me a break. I didn't say, "Give me a break." What I said was, "No, thank you." I have since found that Super Balls are a product of Wham-O, the Frisbee people.
In the book that I mentioned, Roundabout, is an article on rattlebacks, which you spin one way (like a top), and it stops spinning (it rattles for a second or two) and then spins the opposite direction. Honest.
See Why Does This Work? (in my Billiard/Pool pages) for some more comments on Super Balls.