I want to buy a model like this, or something similar to it.
It consists of tiny ball bearings sandwhiched between two layers of transparent plastic. Their behavior is similar to the behavior of atoms in a liquid metal crystallizing.
Anyone know where I can buy one?
Oh, you want PIRA experiment number 1R50.40.
(PIRA, a physics teachers organization has created a Dewey Decimal System for experiments.)
Unfortunately, PIRA doesn’t sell the experiments. Nor do any of the scientific suppliers they link to supply this specific experiment. Nor does anyone on the web.
I have found physics departments which have this experiment on hand for their teachers to submit an order form in order to use on a particular class date. But I don’t know if they loan out to others.
I’m guessing these physics departments asked their engineering departments to create this demonstration for them. IOW, these are all home made, not from some supplier.
However, good news. You can get a video of this demonstration from here.
Peace.
Technically, they’re steel balls, not ball bearings. A ball bearing is the assembly made by sandwiching steel balls in a round channel.
In the McMaster-Carr catalog, 100 1/16" steel balls cost $5.02. 4000, as used in the one moriah linked to, would cost $200.80. The uniformity of the balls would affect the uniformity of the “crystal”, so I don’t know if BBs would be sufficiently uniform. But 6000 BBs retail for less than $9, so it would be worth trying. They are .177", almost three times as large as the 1/16" balls.