Is static electricity different from regular electricity, or is there simply something different about how it is formed and how it behaves? What, for that matter, is electricity? Obviously it involves electrons.
Electricity, Your Ordinary Household Variety
A household circuit is just that. It’s a circuit – a kind of conductive circle that allows electrons to flow through a device that uses some of them to function. Flow is the key. Flow is the word.
Consider a water hose. When you turn the water on, does it trickle out or burst out? The amperage, like the water in the hose, represents the amount of electrons. The voltage is comparable to the pressure of the flow. Finally, flow suggests dynamic energy, energy not standing still, not static.
Static electricity is not usually associated with a circuit. It represents electrons that build up. Consider St. Elmo’s Fire. A ship travels in the open sea and air molecules strike the mainmast. That results in electrons being stripped off atoms to produce negative electrons and positive ions. The electrons have little mass; the ions have much more mass. The ions move on, but the electrons adhere to the mast. They build up until their surrounding allows a discharge.
In fact, mechanical energy (friction) is being converted into electrical energy, you might say. You walk across a plush carpet on a dry winter’s day. Your feet tear electrons away from atoms in the carpet’s pile. You build up a charge. You then touch a metal door knob and feel a shock. Discharge! Static electricity flows from your finger into the knob.
The electricity responsible for St. Elmo’s Fire is minimal, to be sure. In fact, it is the positively charge ions of gas that emit the light.
This short video (3:08) beginning at about the 2:15 mark, shows St. Elmo’s fire, appearing on an aircraft’s windshield…
Lightning, on the other hand, can kill. Is lightning static, since there is no circuit to speak of? Yes! So how can we explain how lightning forms and the reason for the difference in power?
Simply put, moisture in clouds consists of frozen, very tiny ice droplets. These collide with molecules of gas, stripping atoms of some electrons. These can build up. However, there is no door knob to draw that buildup off. It builds up and builds up until finally, it discharges, either to another cloud, or, with sufficient buildup, clear to Earth. Imagine the power needed to accomplish that. It releases so quickly and so violently, a clap of thunder results.
The following short video (2:55) is informative, detailed, and encompassing. A nice, clear presentation!
Electrostatic Generators for Home or Laboratory
Care to experiment with (AKA ‘play around’ with) electrostatic devices? Two of the most common models are the Van de Graaff generator and the Wimshurst machine. These are readily available to an eager enthusiast.
We’ve all heard the tale of how Ben Franklin flew a kite and learned lightning and electricity were really one and the same thing. He came to realize that static electricity was the same thing as ordinary electricity. Do you enjoy a good, educational cartoon? I recommend this one: Animated Hero Classics: Benjamin Franklin