(c) Anthony K. Grafton 2003

Shocking Facts About Electricity

Part I: What is it?

What is electricity? Is it something mysterious that hides in little holes in the wall until you need it? Is it something that Ben Franklin found in a cloud with a kite? Electricity is many things, but it is probably the single most important thing that lets us live in the modern age. So, let’s stop and think a little about electricity.

Electricity is a word we use to describe the flow of electrons from one place to another. Electrons are tiny, sub-atomic particles present in all atoms. All electrons carry a negative charge. When electricity flows through a wire, electrons are using the wire to move from one place to another.

When people talk about electricity, there are some common words used that need to be understood. First, there’s voltage. Voltage is the difference in electrical potential from one end of a wire to the other. To help understand what this means, think of electrons as air, and voltage as the wind speed. Wind is caused by air pressure differences, and electricity flows because of potential differences. Voltage, however, doesn’t tell you everything you need to know about how much work the electricity can do. Consider the difference between the air moving in a sneeze and the air moving in a strong hurricane wind. Both move at about 100 miles per hour, but the hurricane is moving much more air. Which one can do more work?

The next common electrical term we need to know is amperage. The ampere (or amp) is a measure of the number of electrons moving along a wire over a given amount of time. The higher the amperage, the more electrons that are flowing. All electrical circuits can be dangerous, but the higher the amperage, the more dangerous it is.

Consider the difference between a common electrical wall socket (120 volts and 15 or 20 amps) and a common stun gun (100,000 volts and 0.01 amp). The wall socket can kill, because its high amperage moves a lot of electrons in a short time, but the stun gun doesn’t kill, because it operates at such a low amperage. If voltage can be thought of as wind speed, amperage can be thought of as the amount of air moving at that speed. A hurricane has much more destructive force than a sneeze, even thought the air involved is moving at about the same speed.