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jacobs ladder in vacuum chamber

jacobs ladder in vacuum chamber

jacobs ladder in vacuum chamber

(OP)
I teach electrical and heating and air at Vatterott college in Oklahoma City. I conducted an experiment in class with a Jacobs ladder inside of a vacuum chamber. I posted the experiment on you tube.http://youtu.be/ir6r72-s6XU. I don't understand what happened. I was hoping to get an explanation here.

RE: jacobs ladder in vacuum chamber

You created a Discharge Tube. As you reduce the pressure the insulation aspect of the air decreases until the electrons just spew from everywhere. The remaining gas in the chamber is ionized like your typical neon (gas discharge) tube.

You can often predict which gas is ionizing by the resulting color.
See this entertaining site for the colors:
http://www.personal.psu.edu/sdb229/Plasma%20ball%20colors.html

A Jacob's ladder works on thermal convection. The hot arc is lighter than the air it's immersed in, hence it rises up the ladder. You put it in a near vacuum and the driving principal fails as there is no buoyancy available to float the arc.

You should keep in mind is that if your voltage exceeds ~30kV you can start generating X-Rays you don't want exposure to.


Keith Cress
kcress - http://www.flaminsystems.com

RE: jacobs ladder in vacuum chamber

Also - Google for information like corona discharge and Paschen's law.

As it smoked pointed out, you get the voltage high enough you begin to run the kinds of experiments that Roentgen was doing in 1895 when he discovered X-rays.

RE: jacobs ladder in vacuum chamber

I was going to say that you would eventually have an X ray generator, so be careful!

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