What is Electricity: An Intuitive Understanding

We’d like to delve more into electrons and how they are related to electricity. First, perhaps the most important thing you should understand about electrons is that they hate each other. They try and escape from each other’s presence as much as possible and will naturally spread themselves out as much as possible.

Also, while electrons typically whirl around the center of an atom, the nucleus, sometimes they’re not very attached to that either. For insulators, like glass and rubber, these electrons are held fairly tight to the nucleus and don’t want to leave. But, for conductors like copper, these electrons aren’t very tightly held, and where there are a lot of copper atoms together, you can think of the electrons as a sea, with the electrons moving about freely among the atoms.

In this sea, the electrons are always trying to get away from each other, and using this property, you can do work. By shoving a bunch of electrons together in one place, they’ll try and run away from where there are a lot of electrons to where there are less electrons. Usually, when we think of electricity, we’re thinking of this flow of electrons. The normal measurement of non-static electricity is amps, or amperes, which is when a coulomb of charge passes a point in one second. And a coulomb is about 6.24 x 10¹⁸ electrons. In other words, if you have an amp passing through a wire, it means that 6.24 quintillion electrons are passing through each point every second!

As electrons hate each other so much, electrons really want to go where there are less electrons. If we have two objects, the one with more dense electrons is said to be at a lower voltage, meaning that the electrons want to flow from the lower voltage to the higher voltage. This may seem counter intuitive, because everyone knows that current flows from the higher voltage to a lower voltage! Unfortunately, electrons do flow from a lower voltage to a higher. A long time ago, Benjamin Franklin made a guess that electricity flow was from positive to negative and he established the standard direction of current. He had a 50% chance of being right, but he wasn’t. Because of this, current flow and electron flow are opposite. This can be very confusing, but the important thing to remember is that current flows from a higher voltage to the lower voltage, which means that electrons flow from where electrons are more dense to less dense. Also, while there are times that you will need to remember this difference, the vast majority of the time, you only need to consider current.

So, while this is a simplification, when you turn on your light, what you’re doing is that you’re connecting two halves of a light to two different voltage levels and the electrons are moving through the light, trying to move from the lower voltage to the higher voltage and come to an equilibrium.