Build it yourself! Or if not, this device is available through Arbor Scientific. Contact them for a
current catalog and pricing. ( Catalog
page) Even if you don't intend to purchase this device, their catalog
is worthwhile for the science toys and demos.
An electronic device for explaining electricity
A wire with giant moving electrons.
1993 W. Beaty
This device shows us what "electricity" would look like if we could see
All metals are full of movable electrons (a physics teacher would call it
electron sea.") These electrons can be pushed around by a voltage or
"potential difference." Wires act like water-filled hoses, where voltage
is like water pressure, and batteries are like water pumps.
If we could SEE the electrons during electric currents in a wire, they'd
look something like the following GIF animations, although they'd move
far more slowly: