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Chapter Four
Getting Some Static

Q: What did one atom soy to the other atom?

A: It’s Electron Time – time to go to the poles and volt.

Some of you probably remember studying static electricity in high school physics, Electrical Engineering students study it too – about a year and a half’s worth. The interesting thing is that once we learn if t we never use it in our careers, unless we get involved in high-voltage transmission lines and the like. Too bad – there’s some pretty interesting stuff there, including static electricity motors and such.

The reason why I include static electricity in this book is that for electrical play toys, like violet wands and rubbing your feet across the carpet on a dry day, we need to take a look at some basic principles of static electricity.

In teaching us about static electricity, engineering schools teach a lot of theory with fairly complex math. We also do a lot of experiments with pith balls. Believe me, if your balls were made of this extremely lightweight material from trees, you’d be “pith”-ed too.

Understanding basic electrical play doesn’t depend a lot on understanding the models and mathematics of static electricity, so I’ll present it to you in a more simplified manner. Whew!

Static Electricity Rule #1: There are two kinds of static electricity charges: positive, “+” and negative, “-”.

Generally the negative charges are electrons and have been stripped off the atoms in the material. This is actually very easy to do in many materials. Atoms with an extra one or two electrons can also be negatively charged.

If an atom loses an electron, then the atom becomes positively charged. Atoms with more or fewer electrons than they normally should have are called ions.

Static Electricity Rule #2: Like charges repel each other. Unlike charges attract each other.

You’ve probably heard this one before, and some people have even applied it to non-electrical things like relationships. But as far as static electricity is concerned, look at figure 8 to have a picture in your head of the concept.

Static Electricity Rule #3: It is fairly easy to generate a static electrical charge.

Static electrical charges are fairly easy to generate. You can even generate them mechanically. Shuffling your feet across the floor, taking off a wool sweater, or sliding nylon panties off a vinyl-covered stool are all ways that can generate static electrical charges.

Static Electricity Rule #4: Static electric charges are always trying to equalize the charge.

If you have two bodies having opposite electric charges and a gap separates them, they will all ways try to equalize or cancel each other out.

This means that whatever positive “+” charge is out there, it will try to capture an electron or negative charge, This phenomenon is a consequence of Rule No. 2. Because of this it is possible to generate great forces (“great” as compared to the weight of an electron) that can move very light objects like bits of paper or pith balls.

Static electricity, in which positive charges on one side and negative ones on the other try to equalize one another, is pretty easy to generate.

Static Electricity Rule #5: Static electric charges can produce high voltages.

Even though it’s only electrons, static electricity can produce very high voltages – from thousands to millions of volts, We’ll study high voltage effects in the next chapter, but for now I’ll just say that in electrical toys, like violet wands and other high voltage toys, you can get a good idea of the toy’s effect by using the principles of static electricity.

If you shuffle your feet across the carpet in a warm, dry room inside the house on a cold winter day t the voltage from your finger to the doorknob can be 25,000 volts or more.

Figure 8

Static Electricity Rule #6: Static electrical charges move whenever they can.

Because of Rule No. 4, static electrical charges will move whenever they can. They cant move across an insulator, but they can and will move across any conductor The spark from your finger to the doorknob in the “carpet shuffle zap” proves this principle. Here the spark is the conductor allowing the charges to equalize (Rule No. 4). These moving charges – generally the electrons – are the same as current However, because of the limited number of electrons involved, even though the current may be momentarily high, the jump will only last for the short period of time that it takes to equalize the charges. Thus, the “carpet shuffle zap” gives you only one short duration spark rather than a continuous spark.