176: Basic Electronics: Voltage, Current, Resistance.

Knowing some basic electronics helps you become a better programmer. You might have seen warning signs that say “Danger: High Voltage” But do you know what voltage really is? You’ve probably used batteries until they’re dead. But do you know what that means? I’ve talked about high voltages representing binary ones and low voltages representing binary zeros. What are these voltages? Is high voltage in a computer the same as high voltage at a construction site? The way I first learned to think about voltage was using water and pipes as an example. You might think that water is voltage but that’s not quite right. Water will flow from a high place to a low place because of gravity and if you restrict this flow by making it go through pipes, then it’ll build up pressure. This is why towns build water towers to raise water high in the air. It provides a reservoir of water with a natural tendency to create pressure. The water itself in this example relates to charge. The pressure is voltage. The flow of the water is current. And the pipes not only resemble wires but also act as a source of resistance. Let me explain each of these a little more. Listen to the full episode for a more detailed explanation of charge, voltage, current, resistance, as well as Ohm’s Law and how they relate to each other. You can also read the full transcript below. Transcript You might be wondering why I would talk about electronics. This is a podcast about programming and I mean to keep that focus. However some understanding of electronics can actually help you become a better programmer. Especially if you’re programming robots, or 3D printers, or whatever invention you’re working on. Programming is becoming more and more important. And the best programmers will be the ones who can apply their skills beyond the computer and smart phone. I studied electrical engineering in college not only because it was fun and interesting but because I knew that it would allow the most flexibility with my career. I knew that I could continue with electronics or become a programmer. Going the other way is much harder. But exploring just a little electronics is not that difficult. I’ll stick to the basic concepts that I think will help you the most. You might have seen warning signs that say “Danger: High Voltage” But do you know what voltage really is? You’ve probably used batteries until they’re dead. But do you know what that means? I’ve talked about high voltages representing binary ones and low voltages representing binary zeros. What are these voltages? Is high voltage in a computer the same as high voltage at a construction site? The way I first learned to think about voltage was using water and pipes as an example. You might think that water is voltage but that’s not quite right. Water will flow from a high place to a low place because of gravity and if you restrict this flow by making it go through pipes, then it’ll build up pressure. This is why towns build water towers to raise water high in the air. It provides a reservoir of water with a natural tendency to create pressure. The water itself in this example relates to charge. The pressure is voltage. The flow of the water is current. And the pipes not only resemble wires but also act as a source of resistance. Let me explain each of these a little more. Let’s start with charge? Atoms have electrons with negative charge orbiting a nucleus of protons with positive change and neutrons with neutral charge. Atoms have the same number of electrons as protons which cancels the charge and the atom as a whole has no charge. But if you take away some electrons or add some extra electrons, then the atom becomes an ion. Charge is measured in coulombs and it takes 6.242 x 10 to the 18th power number of electrons to get 1 coulomb of negative charge. You can also have the same number of protons to get 1 coulomb of