Fluorescent BulbA classic plasma ball trick is to show how the electric field doesn't actually stop at the glass dome even through that's where we stop seeing it. To make this visible outside of the globe, all you need is a fluorescent light bulb. Any bulb will do but I'm partial to a 12" tube like this one on Amazon. Once it is close enough to activate, it glow just it would in a light fixture! If you have a tube like mine you can even play around with holding it in different places along the bulb show how the charge follows a path to ground rather than illuminating the full bulb. Long Distance GroundingThe most impressive demo in my opinion is to light up a fluorescent bulb using the plasma ball without ever holding it close by. To do this, find a way to insulate yourself from the ground by getting on a wooden chair/table or plastic stool. Once insulated, touch the plasma ball with one hand. With the other hand, hold one end of the lightbulb and touch the other end to a path to ground, this could be a sprinkler head, faucet, or even someone else who is grounded :) To really show that it is the plasma ball as a the source of the power, tapping out a pattern will result in synchronous flashes of light. Plasma PennyEvery year, I have a handful of students that are disappointed that they can't "feel" the shock of the plasma ball in the same way that they do with the Van de Graaff Generator. To help give them this experience, at the end of class, I put a penny on top of the glass globe and power on the plasma ball. When you bring your hand close to the penny, electricity arcs to your finger in a decently painful zap. You can even arc through a piece of paper or post-it and create burn marks. I don't recommend smelling your finger afterward though. It'll give you just a hint of "burning flesh"... Click for more Electricity resources ⬇
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