### Electronics Basics

Based on many conversations I’ve had with people over the years, I’ve come to the conclusion that, of all the elements that go into a car, electricity is, by a wide margin, the most misunderstood. And not just by the layman, either. Electricity is a hang up for technicians and engineers, as well. I've also concluded that a great deal of this misunderstanding stems from the fact that electricity is invisible and formless, so its nature can be perceived only indirectly. Another reason for the misunderstanding is that electricity is not often taught well in many schools, possibly because the instructors don’t fully understand it, either. In the following section, I portray electricity as a phenomenon — which it certainly is — that can be reckoned with and worked with. So, what is electricity? What is this force that sparks the sparkplugs and lights the lights? Is it some kind of magic that only an engineer or scientist can understand? No! Webster’s New Collegiate Dictionary puts it like this: "Electricity is a fundamental entity of nature consisting of positive and negative kinds... usually utilized in the form of electrical currents." Mysterious, maybe, but not magic. Let’s try to improve on Webster: Electricity has positive and negative charges. It is an invisible force. It can be controlled. It can do work. It can flow in a current from place to place. It can flow only in a completed circuit. It can be "stored” in a battery. Pic. When the like poles (+ + or - -) of two magnets are close to each other, they repel. The unlike poles (+ and -) attract each other. This phenomenon is the basic key to understanding how electricity works. Positive & Negative — In grade-school science, you probably learned that magnets are electrical in nature, with a north pole and a south pole. On some magnets, north is marked + (positive) and south is marked - (negative). Put two magnets close to each other and you’ll see that like poles ( + + or - -) repel each other and unlike poles ( + — ) attract each other. This separation into positives and negatives is called polarity. It is the first important point about electricity, which will become clearer later. For now, just remember positive, negative, and the attraction between them. The Invisible Force — You can’t see electricity because it operates at an atomic level. All matter is composed of atoms. They’re so...