A few weeks ago, we put up a "Fermi problem Friday" post about the odds of being struck by lightning. That post was met with some criticism in the comments section, so it's currently down while we revise it to reflect our readers' concerns. But last Friday, we made a discovery here at PhysicsCentral headquarters: your odds of getting zapped go up exponentially if your boss brings her old Van de Graaff generator to work!
|His hair doesn't usually do that (but if he could get it to, he would.)|
A Van de Graaff generator is a device that creates extreme amounts of static charge. It's similar in appearance to a Tesla coil, but markedly different in its construction and function. From the outside, they're strikingly similar; the most common design for both consists of a metal spheroid atop a column that separates them from their base, but that's just about where the resemblance ends. (One is pretty safe to touch during operation...the other, not so much!)
But while the Tesla coil is a precisely-tuned combination of resonant LC circuits, the Van de Graaff generator is as simple as a conveyor belt for electrons.
|That's not an analogy; it's a literal belt that carries electrons from one place to another!|
Image courtesy Omphalosskeptic, CC BY-SA 3.0
|Alike charges on the strands of my hair repel and try to spread out from one another, giving the impression that my hair is trying to get free from my head.|