A Jacob's Ladder visualizes electricity by creating a plasma arc that lets you view electricity itself. This project uses exceptionally high voltages and is very dangerous, and should only be done by people confident in what they are doing and who are not working alone.
This Jacob's Ladder is made with two conductive aluminum rulers that have a 12,000V arc continually rising up between them. If that sounds like a lot of voltage, it's because it is a lot.
I know I may be repeating myself, but I cannot stress this enough - this project is dangerous and should not be attempted by anyone who is unsure of what they are doing or working alone! Always make sure someone is nearby while working on this project.
If it sounds like I am trying to scare you, I am. You should have a healthy fear of the amount of electricity that is required to ionize air, and conduct as plasma across an air gap. This is not a toy.
Anyhow, the way the Jacob's Ladder works is that it builds up such a high level of charge it is able to ionize air, and conduct through it from one wire of very high potential to the other wire of much lower potential. When the electricity travels through air, it is basically an electrical short. Thus, not only is it conducting electricity, it is building up a ton of heat. The heat created by arc, begins to heat the air and creates a heated pocket which begins to rise and pushes the arc upwards.
As the arc rises, the distance between the rods increases, and the arc encounters gradually more resistance as the air gap increases. When it begins to reach the top, the resistance of the air becomes too great for electricity to conduct, and the spark breaks. The result of this is that the charge immediately forms again on the bottom (the path of least resistance), and the process starting all over again.
Confused? Learn more about electricity in the Electronics Class.
For the Jacob's Ladder you will need:
(x1) 22.5" x 11" x 2.7" shadow box frame
(x1) 12,000V neon transformer
(x1) Right angle power cord
(x2) 12" aluminum rulers
(x2) 1/4-20 x 1-1/2" nylon bolt
(x2) 1/4-20 nylon nuts
(x2) 1/4" x 1" nylon spacers
(x2) 1/4" ring terminals
(x4) 8-32 x 1/2" bolts
(x4) 8-32 nylon insert lock nuts