The Mighty Electron

    The electron is at the heart of all life.  Electrons bond atoms together to give us molecules.  When enough electrons are stripped off of water droplets, we get lightning.  Electrons in our neurons control our nervous system and thus they control all life.  When electrons move in atoms, we get light.  Chemical activity is directly related to the sharing of electrons.

All electrons have a force field around them.  They repel each other. This force acts at a distance just like gravity.  To show you how potent this force is, consider two people separated by a few feet.  If one percent of the electrons on each person were free to repel the other one percent, the force would be big enough to move the earth out of orbit.  In other words, the forces around electrons are very, very strong. The gravitation pull between two humans, by contrast, is so small it can hardly be detected.

In most electrical activity a very small number of electrons is involved.  We can see this force when hairs stand straight up in dry weather after a combing. We think of electrical current as the flow of electrons.  It may come as a surprise that the average velocity of electrons in a circuit is only an inch a second.  This is slow.  But we know that electrical signals and power travel miles in milliseconds.  So how do we reconcile this difference?  The answer is that the forces of the field travel very fast.  In other words, when we observe electrical activity we are observing the way the fields move, not the way the electrons move.

To illustrate this fact, consider the capacitor.  A capacitor is two conductors separated by an insulator.  How does current flow through the capacitor? The way this happen is that current flows as a changing electric field, but not as electrons. 

As we try to make our circuits operate faster and faster, we must change the way we view current and voltage.  The explanations that are made by circuit theory begin to fail and we must look into how the electromagnetic fields move.  We live in a world of fields.