High Voltage Motor Experiments

Just running the motor

If you have a safe, current-limited high voltage DC supply, simply connect the output wires from the supply to the commutator wires of your bottle motor. I found that a minimum of 4500V is needed to make the motor barely turn. At 7000V, the motor will spin quite rapidly. DC high voltage power supplies are dangerous, so unless you are familiar with High Voltage and electrical safety procedures, use some other power supply. If you have a VandeGraaff machine, then use one wire to connect the grounded base of the VDG machine to the foil of one stator-bottle. Connect the other bottle's to the sphere of the VDG machine with wire and tape.

Electric Current Through the Air

If you have a VandeGraaff machine or other type of ultra-high voltage source, try attaching a sharp point to its main terminal to create charged electric wind. Aim the wind at one stator bottle of the bottle motor, and ground the other stator bottle with a wire going to a water faucet (or to the screw on an electric outlet plate.) The motor will spin! Start with a spacing of a few inches between the sharp point and the stator bottle. Get the motor to run this way, then move the motor farther and farther from the generator, until it just barely turns. I was able to run my motor (very feebly) from a VandeGraaff machine about 15 ft. away, totally through the microamp currents conducted by the charged wind. When I stood in the path, the motor would stop. An Ion-Beam burglar alarm! If you want to make it work over long distances, a draft-free room is required.

Electric Current Through the Demonstrator

Connect one side of the motor to ground. Stand on an insulated platform, touch the main terminal of an operating VandeGraaff machine with one hand, then touch the non-grounded stator bottle foil with the other. The motor will spin rapidly. You can even run the motor by POINTING at the appropriate stator bottle foil from a few inches away. Charged air streaming from your finger conducts a few microamps to the motor. So, how many people, standing on insulating platforms, can you connect in series and still have the motor run? Leakage to ground, rather than the resistance of the people, would be the limiting factor. Everyone's hair should be standing on end during the demonstration. I've never tried this. You be first!

Running the motor with a balloon

Connect one stator bottle foil to ground. Pass the surface of a charged balloon along the foil of the other stator bottle, and the motor will slowly turn. With several people working, it is possible to keep the motor turning by sequentially charging several balloons and passing each across the foil. Hint: this works better if you place the balloon against the stator bottle at the top edge of the foil, then carefully ROTATE the balloon so its charged surface passes over the foil edge.

The awsome power of Television

Dr. Krienke at SPU in Seattle suggested this one. Use tape to tack a sheet of aluminum foil to the screen of a TV set (leave a 1" to 2" space around the foil, and fold the corners back). Tape the bare end of a wire to the foil connect the wire to one side of the motor, and connect the other side of the motor to ground. When the TV is turned on, the motor will spin a few times then quit. When the TV is turned off, the motor again spins briefly. Capacitive coupling right through the glass picture tube! Turn the TV on and off very slowly, to generate slow AC and run the motor continuously. It would be wise to use an old, half-dead TV, so you don't damage it by turning on and off so much. If the screen lights up and crackles, the TV should work, even if it doesn't receive pictures.

ELECTROCUTION HAZARD! FOR TRAINED PHYSICS TEACHERS ONLY! The demonstration below is EXTREMELY DANGEROUS! Don't try it unless you are experienced with safety procedures used with high voltage at deadly energy levels. If you attempt this demonstration, you assume all the risk yourself, I cannot guarantee your safety. Parents: don't let kids try this under any circumstances! It's intended only for use by trained physics teachers who have experience with the usual safety procedures to be used with Leyden Jar demonstrations.

Stored Energy

Fill both stator bottles with water, and place the two ends of a single wire in the water of both, to electrically connect the water together. Now connect and run the motor as you normally do, however...
DON'T TOUCH ANY OF ITS METAL PARTS OR WIRE CONNECTIONS, OR THE STORED ENERGY MAY ELECTROCUTE YOU!
After the motor begins to turn, carefully disconnect the power supply (use proper safety procedures and protection.) The motor will continue running for up to a minute or two. You have created two Leyden Jar capacitors which can store enough electrical energy to run the motor for a while.
When finished, be sure to carefully discharge the capacitors, to each other AND to the water conductor, then dump out the water before handling it again. Be warned, this demo is dangerous if you don't know how to safely handle high voltage capacitors. If it zaps you, at the very least it will knock you on your butt and make your arm numb for hours. If you accidentally discharge it through your body, it very well might kill you. Only attempt this demonstration if you have done this type of demonstration before, and you know how to work safely with high voltage at lethal energy levels.

ELECTROCUTION HAZARD! FOR TRAINED PHYSICS TEACHERS ONLY! The Stored Energy demonstration is EXTREMELY DANGEROUS! Don't try it unless you are experienced with safety procedures used with high voltage at deadly energy levels. If you attempt this demonstration, you assume all the risk yourself, I cannot guarantee your safety. Parents: don't let kids try this under any circumstances! It's intended only for use by trained physics teachers who have experience with the usual safety procedures to be used with Leyden Jar demonstrations.

http://amasci.com/emotor/emotdemo.html
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