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Jamie Oliver's Tesla Coil Dem Outline Page: ©


Two Talks:

I have two outlines, one is for a talk with technical adults at a higher level and one is for a general audience with children as low as age 4 up to senior citizens. The outline below is the general audience outline. If you have any suggestions or commentsfor items that you have found that interests any age group, please mail them to me (tesla@frontiernet.net). I'd appreciate it.

I worked hard to make this list and refine it over the years. If you use it, please credit me for it. It is copyrighted. My reason for posting it is that I want to advance the sciences to kids as much as possible. See my comments here. Last updated Oct 2005.

Safety Requirements Before Running a Tesla Coil in Front of a Group:

  1. You must make sure it is safe for you and everyone else.
  2. For $5, buy a power outlet checker (this thing has 3 lights on it and tells you if your ground, neutral, or hot lines are reversed) at your local hardware store. If you plug your coil in and don't have a good ground wherever you are running your demo, you could kill yourself or someone else.
  3. Before you turn on your tesla coil, you must ask everyone in the audience if they are using any biomedical device (pacemakers, portable dialysis, etc). I say they should be 50 feet back for my 1800 watt coil.
  4. Fire Control Sensors should be at a good distance away from the location of the coil. When I setup at our museum I had a sensor about 20 feet away on the ceiling and waited for after hours with security to turn off the fire control alarm and then we tested it at full power. The last thing you want on the news is your name responsible for emptying out a museum of 700 people and I'm sure your sponser would not appreciate it too.
  5. Before you turn on your coil and before you close with folks, you have to tell everyone that this is really dangerous and no one should attempt to play with wall power or high voltage without being fully trained in electronics

Starting Off:

  1. Intruduce yourself
  2. Tell about how long you have been involved with electricity and what qualifies you to talk about Tesla.
  3. What "sparked" your interest in electricity?

Suggestion for Talking with Kids:

One general presentation hint I learned from my friend Calvin is that the best way to ask kids question about anything is to ask them "what do they feel is...." This way, they are less likely to feel "wrong" in front of a group. It facilitates a more interactive and fun atmosphere for a demonstration.

Some History of Tesla:

  1. Born in Europe, Croatia (Smiljan village, district of Lika) in 1856 (I would highly recommend reading Magaret Cheney's Book on Tesla)
  2. Father wanted him to be a priest like himself.
  3. Saw a model of Niagara Falls and knew then that he would harness the power of the falls.
  4. Had the idea and concept of the Induction Motor and his school professors told him that his idea of a motor without brushes was ridiculous and as impossible as a perpetual motion machine.
  5. Came to America with an Engineering degree and recommendation for work from one of Edison's friends from Paris.
  6. Had an interview and went to work for Edison.
  7. Tesla tried to convice Edison of the need for AC power distribution but Edison would have no part of it.
  8. Tesla left Edison after Edison refused to pay a $50,000 promise after 6 months of work by Tesla. Edison said it was "joke" and that Tesla would need to understand "American humor."
  9. Was out of work for a year digging ditches.
  10. Started a business and patented his Induction motor that would change the world. This is a great spot to ask the audience how many motors do they feel are in their house. There are likely to be over 100 motors (7 in the average PC, CD, VCR, fridge, kitchen appliances, furnace, toys, etc.)
  11. Tesla hooked up with George Westinghouse to produce his induction motors in volume and paid Tesla royalties. Westinghouse would always be Tesla's friend.
  12. Worked together for 5 years to build the generating plant at Niagara Falls.
  13. The "War of the Currents," Tesla's AC power distribution and Edison's DC. Lots of history here. One could elaborate on Edison's vindictiveness and how he electrocuted an Elephant on camera to show how deadly Tesla's AC system was. It didn't even kill the Elephant and DC would likely do the same thing.

Tesla's Inventions:

I start off this session by quizing the audience about what inventions are in the room that Edison invented. Many rooms or auditoriums have fluorescent lighting and frequently none have incandescent lighting. Incandescent is Edison's invention of course. I point out the the lights in almost all classrooms is Tesla's invention.

Some of Tesla's inventions are:

  1. The induction motor (have an induction motor and a brush motor to show taken apart)
  2. fluorescent lights (if it is a young crowd, show and describe the differences)
  3. AC Power transmission. (describe what the world would be like if we were powered by DC)
  4. First remote controlled Submarine
  5. Over 700 Patents, patented a helicopter.
  6. Radio, although disputed, Tesla currently holds the patents for the first Radios.
  7. The Tesla Coil, a Double Tuned High Voltage, High Frequency, Resonant Transformer.

ELECTRICITY: the control and manipulation of electric and magnetic fields.

  1. Explain the types of Electricity, static, DC, AC, Frequency. (There is alot to talk about here. A fun starter that works best if the air is dry and you have a carpted area is to get two volunteers from the audience and have them do a static electricity demonstration. You need two people and two fluorescent lights. Get each volunteer to hold one end of both of the lamps. Turn off all the lights, wait about 15 seconds for peoples eyes to adjust to the darkness and then have the volunteers scuff their feet as fast as they can. The lamps will flash dimly but will be easily seen. You can then talk about static electricity, voltage levels, etc but don't bore them out of their minds (I must use restraint here). I like touching on frequency. I bring a simple bell and ask them "what is going on" when a bell rings. It is a mechanical resonance. Make note of that when the Tesla coils is shown.)
  2. Explain the relationship of Voltage, and Current. (I do this by describing a garden hose and a fire hose. The voltage is the pressure in the hose. High pressure (high voltage) in the hose gives you alot of water (current) flow and low pressure (low voltage) gives a little current flow. When someone opens the valve (open the light switch), the current starts to flow and energy/power is flowing. Frequency is when the water is flowing back and forth in the hose, but that isn't as easily visualized).
  3. The Electric Field. I explain that everyone has played with a magnet with a magnetic field but most people have been zapped by generating static electricity. This is where I start the Tesla coil with the rotary spark gap set to a very small gap (maybe 0.020 on a side) as to limit the maximum voltage out of the coil. I turn up the variac so it is firing but have no sharp edges on the coil so there are no sparks eminating from the coil. I walk around with the fluorescent light in my hand and show that it can light at a good distance, 3 meters or so. Also what is really cool and the audiences really laugh over is that if you have young kids that have sneakers with the LEDs in them, they will light up being triggered by the electric field of the coil. Most kids will volunteer a sneaker for this but not always.
  4. Resonance, what a capacitor is and does and what an inductor is and does. How they store energy in them and transfer this energy back and forth like a bell does mechanically.
  5. Frequency and skin effect. I can't recommend this for ANYONE as it is NOT safe but I talk about skin effect and what it means in a conductor and to show this I get a fluorescent bulb, hold it with overlapping hands, stand on an insulated 5 cm. base that has aluminum tape on it and have the arcs from the coil hit the lamp, light the lamp, go through me to the base and jump the 5 cm gap to the floor or grounded plate on the floor. After that I also hold my hand about 20 cm from the torroid and show the arcs jumping from the tips of my fingers.
  6. Plasma! Many schools are taught 3 states of matter. Be careful NOT to upset any teachers there on how you present plasma. You can say this that kids are taught 3 states of stable matter and that plasma is an unstable state of matter. With the Tesla coil still at the low gap setting, get a soccer ball covered in aluminum foil and set it on a grounded plate and put it close enough that when you turn the power up to your coil that the air will start to break down and turn to a blue glow. Describe what plasma is and how it forms. Ask them if they have seen plasma before (lightning).


  1. Read about how lightning works first. This is a great site.
  2. Step Leaders,
  3. Streamers,
  4. What is a Lightning Rod and how does it work. Like in the plasma demo above, show how a sharp point using a piece of thick wire (like a sharpend hanger) and a ball covered in aluminum foil (smoothed out as best as possible) sitting on a metal plate act. (See this picture) When you do this, the arcs forming from the tesla coil will jump to the lightning rod much more than the aluminized ball. Explain that this is because of the sharp point phenomenon of the lightning rod. Put a section of aluminum tape or lay a wire on top of the torroid to show how it leads a strike too.
  5. Talk about Lightning safety. Talk and ask about what is safe and what is not. Can they talk on a wireless phone? (yes), a corded phone (no), take a shower (not recommended), sit under a tree (big no), sit in a car (big yes). What is the safe position to be in if you can't get to a building and you are stuck out in a field. The position is feet together, crouched down, head between your legs, hands over your ears. Discuss and show them why and correlate it to the demonstration. Is it safe to lay down on the ground in a lightning storm? NO! If a strike is nearby, the voltage gradient on the ground is high, possibly many thousands of volts per linear meter and you DON'T want it going through YOU!
  6. The Umbrella Demonstration! After showing the lightning rod demonstration emphasising how a sharp point atracts electron dissipation and therfore you don't want any sharp points like jewelry, glasses etc, show how people walk around with sharp points with an umbrella. Get an umbrella and with double redundancy grounded wires, hold the umbrella next to the coil on a light setting and show where the lightning hits. If you want to make it more exciting, grind the tip of your umbrella to a really sharp point to make it more impressive.


I open up the gap on my rotary spark gap to max out the voltage and really pump up the power to the coil. I open the gap using a custom thickness calibrated gap gauge. I designed the rotary so it is easily accessible to do this. Run the coil with no tape or sharp objects on the torroid so the arc breaks out all over the place at random. Then show it with a wire and focus the power to a grounded object or plate.

At a demo at a school I asked if someone (a kid) wanted to come up and stand under this at full power. I did it to see the reactions on the teachers faces which was fun. I had kids ready to run up and try it. I tell them they are very trusting, if you get no volunteers, then you can tell them that they are very smart!

Ask them if they want to try any experiments with the coil. Joke about not doing any experiments with their siblings.

Close with a SAFETY WARNING:

Some folks may have come in late and re-emphasize that NO ONE should attempt to play with the power in their home under any circumstances. If they do want to learn more, have them contact their teacher, parent, ham radio club, or make yourself available to answer questions in the future.

For more educated audiences, you can go into facts like it is current that kills. 4-8 mA can stop one's heart. Shocks can kill many days later, they are not always ok after a shock. They should be checked out at a hospital, EKG etc.

Electricity can kill. A student at a local school here in Rochester was trying to build a Neon Sign Transformer (NST) Tesla Coil and the kid had a flashover or something and got the brunt of the transformer output and his parent found him laying on the floor. He lived but the Tesla Coil project was out of the house immediately. He was "lucky."

Suggestion to Parents:

A suggestion for parents of kids present (or kids to tell their parents), suggest to them about the Radio Shack 50-in-1, 100-in-1 or whatever they are up to, electonic project kits. These are the boards that have a bunch of components with spring clips that allow one to make a whole bunch of cool electronic projects. Fantastic way to have fun learning electronics.

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If you found this useful, please drop me a message. I put alot of effort into this page for making a good presentation. I still suck at my delivery but it is getting better with practice.


  © Copyright 2006-2017. Jamie Oliver  -  Contents of this page are the sole responsibility of me, Jamie Oliver, and no, I'm not the British "Jamie Oliver, The Naked Chef" but I'd enjoy meeting him some day.