I made a bunch of water beads because I wanted to record the sound of squeezing them. It turned out that there wasn’t much. Then, I dropped a bunch on the floor and that gave me an idea.
I think that to get them to really hop about I’d need a higher energy vibration. My hope was that they’d bounce around and sort of look like the molecules of water whacking around in a space, as the water evaporates. Close!
One problem I have is that the more experienced I get with light and stuff, the more persnickety I get. I went over to the studio expecting to bang this experiment out in about 20 minutes but instead I worked on it for 2 hours, and got beads all over the floor.
Hahahaha, fun! I’ve spilled those little buggers, have fun collecting them all.
Caine@#1:
I’ve spilled those little buggers, have fun collecting them all.
I reconstituted some large ones (2″!) and they didn’t work very well – when I threw them into my container, they shattered. I assume that when they dry they’ll be little crunchy bits of powder.
The smaller clear ones make a “wzoop!” noise going up the vacuum cleaner.
Those little ones, when they dry out, they do not shatter. The rats, well, one rat, Angel, managed to get up on a high shelf, and knocked down a jar of them, and I’m still finding them all over the place, about a month later. In their dry state, the rats don’t find them interesting. Just when they are plump and smelling of oranges.
I hope that all chemists will note that this video would be an excellent intro to covering Brownian Motion, which was the topic of one of the four papers Albert Einstein published in 1905. I will try to use this in the college chemistry class I’m teaching this fall, in the thermodynamics chapter. If that’s ok? Thanks.
We might also want to use the video next semester, when we cover the energy of hydration, when discussing precipitation equilibria.
Bruce@#4:
That’d be awesome.
I wish I had a more powerful vibrator; I could probably demonstrate the motion at a variety of speeds up till the point where they are bouncing out the top. That was what I originally was hoping for…
If I recall, from the Feynman lectures on physics, that he explained evaporation as that sometimes molecules moving in brownian motion would whack against eachother just right so that the energy imparted was enough that it’d fly off and not come back. Something like that, anyway.
If you think it’d be worth it for me to try with the larger “molecules” and maybe a bit more cleverness on the vibration platform, I probably can. It’d be an excuse to mess with stuff!
You could do this on a large loud speaker laid flat and a signal generator to your amp.
I had never even heard of these things til this post.
The internet is singularly uninformative about them though there appears to be lots of places/people happy to sell me some.
How do you make them? The best I could find was a wiki that suggested a polymer and water. Does one put the polymer in a bowl and add water while whisking all the time?
jrkrideau@#9:
Let them sit overnight in clean water, they suck it right up.
Lofty@#8:
You could do this on a large loud speaker laid flat and a signal generator to your amp.
Yeah, I was thinking of that. I don’t have any large loudspeakers, though.
Yep, beads all over the floor.
Raucous Indignation@#12:
Yep, beads all over the floor.
A helpful friend suggested I de-balance a circular saw blade and mount it in my table saw, then use that as a vibration source. I have such thoughtful friends!