The way this works is very simple. The tube is held in one hand, while the other hand slides the fur back and forth along its length. 1/2", 3/4", and 1" PVC pipe all work, but you need at least a two and a half foot long section (three foot section is even better).
In the photo above the fur is surrounded by a short piece of foam pipe insulation held on by a rubber band. This makes sliding it back and forth a little easier. If you do this make sure that your skin touches the fur or cloth somewhere. In theory the fur is leaving electrons on the tube. You will be able to leave more electrons (generating a stronger charge) if the fur can replace electrons it has lost by getting them from your body.
Another explanation of how to make
one of these is at this site:
Benjamin Franklin used a tube similar to this when he first started experimenting with electricity. His tube was glass, but the operation was the same.
To charge a Leyden jar with one of these: Set the jar somewhere so that the outside surface is grounded (not on a glass table, not on a plastic container, etc.) or have some one hold it (better). Get your static generating tube and hold it so that the tube is right above the ball on top of the Leyden jar. The closer the better. The hand holding the sliding pad stays still. I find it helpful to anchor that elbow by setting it on the table. The other hand slides the tube back and forth. This part requires some finesse: You have to draw the tube across the ball on the jar so that the charge on the tube "goes into" the jar. If you listen carefully you can hear this happen and in a very dark room you can see it (give your eyes time to adjust). There is no problem if the tube touches the ball except that you might knock the jar over. After several strokes the charge that builds up is sufficient to create a visible spark when the Leyden jar is discharged.
Other experiments that use the static tube: This
tube works great for demonstrating the attractive and repulsive powers
of electricity. If you charge it up and hold it over bits of paper or other
light material it will pick those things right up. If you hold it over
an arm it will make the hair stand on end.
A dramatic way to demonstrate repulsion is to hang a (rubber not mylar) balloon by a string then charge the balloon by rubbing it with fur. Move the charged tube near the balloon and you see very clearly that like charges repel. You can do similar things with ping pong balls on a foam plate, or perhaps a plasic soda bottle.
to the Static Generator Page
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