Lessons: #1 Circuitry Super Basics

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Ok, so while we're on the topic of cool gadgets like projecting keyboards and remote controlled paper airplanes, why not talk about how they work? I bet you're curious as to how the guts of these contraptions make them do what they do, so... I'm going to teach you! But before you get to understanding something complex like a projector, we need to start with the basics.

Look at the picture to the right. Kind of obvious what's going on here, right? You have a battery that powers a bulb. Now, this picture isn't correct for a few reasons but I'll discuss those later.

There are two ends to the battery: the positive end and the negative end. When a circuit is formed, the electrons flow from positive end to the negative end; powering any components that come between them. Well, that's how we initially thought it flowed; but further study showed electrons flowed from negative to positive, but it was too difficult to change the math equations we had already formed to fix our mistake so we continue to think it flows the wrong way. So, any way, there are two more broader classifications of electric flow out there. There's AC voltage and DC voltage, or alternating current or direct current. There's basically only one difference and that's how they travel. Direct current is the kind of electricity you'd find pumping through your phone or flashlight. This electricity flows in one direction; kind of like water flowing through a pipe. Now, alternating current does something funky. Imagine you have that pipe of water, but instead of the water constantly flowing in one direction, it sloshes back in forth. It goes forward then back, forward then back. It still moves in a general direction, kind of like taking two steps forward and one step back. You'd find AC in your outlets.

Hopefully, you very vaguely know how electricity flows now. So, why do you think the diagram above is false? Think about it. That light bulb was probably made to be powered from an outlet, but it's hooked up to battery. What's the difference? Batteries supply DC and outlets supply AC! Plus, outlets supplly much much more power than a dinky little battery.

So, want more? Go on to lesson two!