Another We Are Lousy Scientists posting.
We made a bouncing ball. You need borax, cornstarch glue and water. The instructions also tell you that you need a lot of other things like a cup that you mark as having your borax mixture and a cup you mark as having your glue-cornstarch mixture and things like a watch with a second hand. I actually paid attention to some of this, like the watch with the second hand business. Who has a watch with a second hand? I don’t even have a watch. I still have in my purse the watch we timed my contractions with when H.o.p. was born (call me sentimental) but it was a cheap one and hasn’t worked in a long while. It had a second hand. I pulled it out and nope it still doesn’t work. I could have looked up some computer second-hand deal on the internet by which to do the timing but by then I’d realized you use the second hand to time the 10 to 15 seconds you let the borax and cornstarch sit together. Never mind. Just count it out.
I have H.o.p. read me simple instructions to things. “Here, what does this say?” I tell him I dont’ have my glasses on and can’t read it, which is sometimes true. But I could get my glasses and it’s instead just plain practice reading and to impress upon him the importance of knowing how to read instructions. When we were getting ready to do the bouncing ball I had him read me the instructions and he didn’t care for that because they wouldn’t result in brownies or blueberry muffins but he made the effort. He read that we would need two tablespoons of warm water and half a teaspoon of borax and he read about how much cornstarch and glue we needed to mix together and he started to try to read the rest but didn’t get much further.
I mixed up the borax and water. Then I mixed up the glue and cornstarch in a second cup. One tablespoon glue and I forget how much cornstarch. It was obvious this was going to be a very small bouncing ball. One is supposed to take 1/2 a teaspoon of the borax mix and toss it in with the cornstarch and glue and let it sit for 10 to 15 seconds. H.o.p. instead enthusiastically poured in the whole thing. None of it absorbed quickly so I poured most back out and told H.o.p. that was a good example of why one needs to really read the instructions and pay attention to what they say. Then we waited 10 to 15 seconds and then H.o.p. took the mixture and kneaded it into a ball.
It was so dry that I unscientifically threw in a dash more of borax solution a couple of times. H.o.p. was well aware we weren’t supposed to be dining on this and eagerly washed his hands when done.
We looked at the bouncing ball we’d made. It didn’t look very promising. H.o.p. wasn’t looking very pleased with it all either. He is mostly bored by science if it isn’t a fake volcano blowing up. He likes that. But you can only build so many fake volcanos and they are painful partings when they go into the trash.
Wanna bounce it? I asked him.
He bounced it. And it bounced. Not a lot but just enough to make him happy.
“I want to paint it!” he said. I said well if he painted it that would mean we wouldn’t be able to bounce it for a while and I wasn’t sure how well this mix would take the paint and I wasn’t sure if the water from the paint would be enough to make it less bouncy. He reconsidered.
We sat on the kitchen floor and played with that little ball for quite a long long time. It seemed to have a livelier bounce if you threw from the side instead of splatting it from above. Never bounced higher than around 12 inches but throwing it from the side it gave it the opportunity to bounce further. He chased it repeatedly under the refrigerator. It had enough bounce that you could have played jacks with it if the jacks weren’t too far apart. We have no jacks (used to, don’t know where they went) but we still pretended to play jacks. H.o.p. thought all this was very funny.
H.o.p. crawled into my lap and held the ball up for us both to appreciate. “We made that,” he said.
“Yup.”
“This will be a great toy,” he said.
We’ve made lots of things, we’ve done lots of little science things, but it did impress him that we’d made a bouncing ball. I was wondering why.
So H.o.p. decided this was really cool. He liked this a lot that we had made this bouncing ball. He wanted to save and protect it. I got a plastic bag for him. He carefully put it in the bag and zipped up the bag and gently put the bag away on the table. He liked that bouncing ball.
I told him what we had done in the name of science. He couldn’t have cared less about that part.
Later I was passing by his ball and saw that he had flattened out on its own. It now has the shape of an almond cookie. Perfectly flat bottom. Gently rounded top. He’s going to be disappointed. Would it still bounce? I tried it out. Yep, still bounces. No bounce at all to the flat side but still bounced around 12 inches on the rounded area.
As usual I found better info on the net than given in the experiment we used. Like what’s explained in this ball experiment that makes use of the idea of a magician’s having balls that look alike but one bounces and the other doesn’t. And then better info also at Virginia Edu.’s “How things work” page on bouncing balls.
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