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Ask HN: What are some good resources to learn how electricity works?

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Re: Ask HN: What are some good resources to learn how electricity works?

#161
Best way to understand volts vs amps is a gravity analogy. Pulling electrons away from protons takes energy, and stores it, the same way that taking basketballs to the top of a cliff does. The voltage is the height of the cliff. The amps is how many basketballs per second you're dropping.

Re: Ask HN: What are some good resources to learn how electricity works?

#164

Earlier quoted context omitted.

I'm not sure I completely agree with this: electronics refers specifically to (essentially) anything concerning the control/emission of electrons (so transistors, thermionic valves, etc.); it's not just "advanced electrical engineering". The divide you're talking about exists in both electrical and electronic engineering, if they are to be considered separate disciplines: in electronic engineering you have both the s…

Electronics is about building useful circuits. Do you really need to understand what precisely happens within any of the parts? No, not really. I can't imagine what happens to electrons in MOSFET nor do I care. For my purpose it represents some transfer function which is what I use to build the circuit. When I think about OpAmp, the physics is not one of things I am thinking. My mental model of OpAmp has no physics i…

EE degree here to back you up. I believe you're correct, electronics is to electricity what software engineering is to CS. It's the practical application with as little depth as you can get away with. For example there's some bits of RF you'll learn when you look at 45 vs 90° PCB traces, but you don't need finite-difference time domain equations to understand what's going on.

Re: Ask HN: What are some good resources to learn how electricity works?

#165

I'm showing my age here, but I got my start with the series of books by Forrest Mims that were available in Radio Shack stores since the 70s. They are written to be understood by complete novices, and they have hand-drawn circuits with everything explained. http://www.forrestmims.org/publications.html

Did anyone else have a "rest of the fucking owl" experience in the first few pages of those books? It was like: Step 1. Here is a resistor. Now, Step 2 here is an AM radio circuit.

That's how I feel every time I try to learn how to use APIs. All the tutorials are like "Here's what REST means" and then "Ok so here's JSON, but we're not telling you what we typed in to get this or what to do with it".

Re: Ask HN: What are some good resources to learn how electricity works?

#166
post #157

Earlier quoted context omitted.

The Art of Electronics is also fantastic

This book ruined many hours of my childhood, when I was in high school. I read it. I didn't understand it. I reread it. I still didn't understand it. At the time, I didn't realize I needed to know basic differential equations, and I just felt dumb. Then I went to college. When I looked at it as a more mature engineer, I found it imprecise, sloppy, and also not very helpful. It doesn't embody good design practice, giv…

Thank you this has been very consoling to read as someone who tried and failed many times with this book when I was young. I thought I was just not smart but now realize most people on the internet who get this stuff are not brilliant autodidacts, they are just educated adults. Even reading a datasheet which is so critical was out of my reach (or patience) without the math and vocab.

Re: Ask HN: What are some good resources to learn how electricity works?

#169

Earlier quoted context omitted.

Electronics is about building useful circuits. Do you really need to understand what precisely happens within any of the parts? No, not really. I can't imagine what happens to electrons in MOSFET nor do I care. For my purpose it represents some transfer function which is what I use to build the circuit. When I think about OpAmp, the physics is not one of things I am thinking. My mental model of OpAmp has no physics i…

EE degree here to back you up. I believe you're correct, electronics is to electricity what software engineering is to CS. It's the practical application with as little depth as you can get away with. For example there's some bits of RF you'll learn when you look at 45 vs 90° PCB traces, but you don't need finite-difference time domain equations to understand what's going on.

Exactly. I know enough physics and mathematics to know that what is used to create designs is laughably simplistic and oftentimes incorrect knowledge. But it doesn't matter, we are not pushing physics with the designs. We just want enough heuristics to be able to build something that works.

Electronics engineers don't go wielding equations to build circuits (well, except maybe Ohm's Law) but rather rely on intuitive models they have in their brains of what components do when put in a specific place in the circuits.

This is necessary shortcut because otherwise even simple circuit can become extremely difficult to understand if you start from first principles.

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