I've tried several times to understand the vocabulary and concepts of electricity - basic things like volts, amps, resistance - but I'm not having much success with self-led study. Can anyone recommend any good videos, books, courses, etc.? Thank you.
Wow, I'm so happy to see this is the first result (the reason I came to comment.) I've tried and failed many times to pick up a fundamental, from the ground-up understanding of electronics and electrial theory. Forrest Mims' "Getting started in electronics" was good, but the All About Circuits text book had the depth and accessibility and I was looking for.
Mechatronics text books tend to be useful. They are written for mechanical engineers who intend to build circuits and software for mechanic-electronic systems. So they tend to have practical information for those who want to start building electronic circuits now, but have no electrical background.
Flipping through, I think the thyrister treatment is a bit weak, and I would ideally like to see more in terms of comm-sys, (like how NTSC works for analog/radio TV), but this looks solid.
The Minecraft mod Electrical Age is surprisingly useful to (literally play around and) get a feel for things. It was originally designed to teach electrical engineers once upon a time. Currently it's been a bit gamified -sure-, but the core MNA solver is still there.
Still somewhat surprising to me, this kind of simulation actually does help. It turns out that you actually do pick up a lot of intuitive feel that can serve well in an industrial context. I guess no matter how much theory you study on, it's still really insightful to just blow up some circuits. ;-)
Note that Electrical age currently works with older versions of minecraft (1.7) , though a rewrite is in the works.
I'm on the opposite side of this question. I've offered to explain motorcycle charging systems in terms anyone can understand. My thought is to use the water flow analogy. Voltage => pressure. Current => flow volume. Resistance => constrictions in the system (or things where the water does work.) Flow at one point in the system must match flow in other parts except for places where water can accumulate (battery => pressure tank.)
My biggest issue is how to depict this in a format that I can share over Skype without putting in 80 hours of work. I might go with a series of pencil drawings and scan them in.
Are any of the suggested materials particularly suitable for this kind of presentation? This is intended to be a 20 minute or so presentation so I'm really just providing highlights. Points I want to get across include:
- Resistance anywhere in the circuit will cause problems. (e.g. bad ground connection.)
- Bad starting can be the result of a insufficient battery charge.
- Bad starting can be the result of high battery internal resistance.
- Bad starting can be the result of high resistance in the circuit.
- Operating with loads (e.g auxiliary lights and heated vest) that draw slightly more power than the charging system delivers can work for hours until the battery is discharged and the charging system no longer supports the loads. (DAMHIK!)
Bad starting can also be a result of physical resistance in the engine, especially as temperatures fall below the normal operating range. When engines get cold enough they put enormous load on the starter motor which has to draw more amperage to compensate.
I think it's very important to teach people that moving electric charges, represented by current, result in magnetic forces, and that these magnetic forces are what cause motors to turn. And an alternator or generator reverses the relation by spinning a magnetic field to generate current, which is why it charges a battery.
I've got quite a lot of experience teaching electricity at a high school level, and I'm also a (relatively) newly qualified motorcyclist with a lot to learn. Maybe we could be of use to each other? If you'd like to get in touch, my email is in my HN profile.
The pressure analogy is a really good one; the problem is a lot of people don't understand water pressure any better than they understand electricity.
I recommend having a look at "Practical Electronics for Inventors" by Paul Scherz and Simon Monk. The book offers a very good introduction about the basics of electricity with many helpful illustrations, written in a down-to-earth style. In case you are interested in electronics, you will find that the book covers many intermediate/advanced topics such as operational amplifiers with lots of practical examples.
I came here to recommend the same book. It's not an easy book though to read from cover to cover though. I found it useful to try to understand a completed circuit design (say for a solar controller or something else I was interested in) and when I ran into something I didn't understand I'd then open up that book and read areas that were relevant.
If you want to begin with the basics then I highly recommend Khan Academy, starting with "Electric charge, field, and potential" [0], then "Circuits" [1], followed by "Electrical engineering" [2].
I personally learned a lot from sparkfun's tutorials. The format is pretty digestible, there are some good videos, and it links out to a few other good resources as well.
I second this. Hobby focused content might seem amateur but it has some advantages in my mind.
Context: My biggest gripe with traditional education is lack of context for why a principle is important or useful. Not a problem when you are focused on a project.
Practicality: The practical aspects of theory are usually limited to core principles and help you see through the fog of all the details.
Narrative: Bringing many topics together in a project narrative give a linear path through the related principles which is less overwhelming.
https://hackaday.com articles, in my experience, have been a good jumping off point and often have solid links for better understanding.
A weakness of this approach is that it ignores the mathematical techniques to solving some of the problems. I doubt you will learn how to analyze circuits with differential equations or phasor analysis on a hobby site. That said, I rarely use these tools outside of an academic setting.
I'm sure someone will recommend The Art of Electronics. Its a great resource once you have the basics under your belt, but hard to use as a learning tool without prior knowledge. It touches on a lot of details by presenting a circuit and summarizing key points about its operation.
Once you have a handle on the basics I highly recommend playing with some circuits in a simulator. LTSpice is free and very high quality. There are other online options too.
You can experiment on hardware relatively safely if you stay away from high voltages and currents (avoid mains power and car batteries, always use circuit protection such as fuses). You will be frustrated if you have no test equipment though, a multimeter is a must-have.
Sparkfun and Adafruit schematics are a great source for learning, too. I designed an I/O shield (with optoisolated inputs and relay outputs) with their open source hardware as the main learning material, and I was delighted that it passed the review of an experienced EE!
First, it is important to distinguish between electricity and electronics.
The difference is like being physicist and mechanic. Do you want to be physicist and understand electricity as a phenomena or do you want to be an engineer and use it for something useful. Believe me, there is less overlap than you think.
One good resource I have found is series of articles on http://amasci.com/ele-edu.html which mixes a little bit of both worlds.
Hmm. What level do you want to start from, and do you want to start from a practical/experimentalist viewpoint or go straight to the mathematical models?
How comfortable are you with "lies for children" oversimplifications of things that are extremely complicated but mostly irrelevant except in edge cases? (This phrase sounds perjorative but isn't, most of the time you don't need the complicated version and it actively impairs understanding what's going on. But it can be the only way to properly answer some questions like "what is electricity?")
I just want to weigh in and say that fantastic as _The Art of Electronics_ is, it is _not_ geared for learning about electricity and electric circuits. The first 13-ish pages (3rd edition) deals with electricity and then quickly moves on to signals, electronics and everything else needed to _develop_ electronic systems.
While AoE (and the newly released X-Chapters!) is an excellent handbook to keep around, I would agree with the other commenters that it is not a particularly friendly textbook for a beginner.
I got a lot from the articles on amasci.com by Bill Beaty. He's done a lot of experimenting, reading, and thinking about this stuff and how to explain it. And is a gifted communicator.
Great essays on understanding electricity, current, voltage, capacitors, transistors, batteries, static electricity etc etc, and popular misconceptions.
Thanks thanks thanks, I read the article about why three prongs long ago. Every now and then I want to say the same article to someone else but did not remember where I read it.
There is also one about different types of plugs in Europe and UK which I cannot find
Walter Lewin's electromagnetism course from MIT [0]. These lectures completely transformed my understanding of physics. He mixes practical demonstration with a rigorous mathematical underpinning in a way that doesn't over simplify things.
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.
Hyperphysics presents a organized tree-like view of concepts, terminology and examples. It's easy to click around and start building up a mental model of how things relate: http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
I remember in high school I had trouble getting it because I thought ohms law had too many variables. Then I realized that a 5V supply will always be 5V in normal operation and ohms law means the current varies.
All of the water analogies were unhelpful for me. I did better just doing the math and seeing the result.
Someone else mentioned MITx. I did that and it was revolutionary. I also have a pretty good book called Practical Electronics for Inventors.
> Then I realized that a 5V supply will always be 5V in normal operation and ohms law means the current varies.
This is a great observation. I've often thought that teaching Ohms law as I=V/R would lead to less confusion. Similarly, in intro physics why is mass acceleration introduced as f=ma? Wouldn't a=f/m have a clearer meaning?
> All of the water analogies were unhelpful for me
Same here, I just had to come to accept that there were orthogonal dimensions/measurements. It didn't matter if I understood them intuitively, as long as I worked with them orthogonally and in strict accordance with the basic equations.
= Geared a little more towards mechanical engineering, but Jeremy Fielding on YouTube has helped me understand some of the concepts with examples rather than textbooks. https://m.youtube.com/channel/UC_SLthyNX_ivd-dmsFgmJVg
= For straight up electric concepts, I’d look at the Georgia Institute of Technology stuff on Coursera. “Introduction to Engineering Mechanics” and “Linear Circuits 1” were helpful.
The training program offered by the US Navy is quite good. Because they can only have so many people on a ship, the Navy tries not to be as specialized as the other services. So, electronic techs are expected to have especially good foundational knowledge so they can work on a broad variety of equipment.
Nobody seems to have mentioned a book that appeared here 19 days ago.
[Letters of a Radio-Engineer to His Son (1922)]((https://news.ycombinator.com/item?id=23358380)). It explains electricity without any technical jargon. Pretty nice first read. His atomic model is outdated, but that doesn't seem to interfere with anything. After reading the first initial letters, you might have a greater motivation to dive into more complicated texts.
[+] [-] basjacobs|5 years ago|reply
It starts from the very basics and builds up to quite complex circuits and their workings. It's an all-round great website, too.
[+] [-] randylahey|5 years ago|reply
And it's free!
[+] [-] peterwoerner|5 years ago|reply
[+] [-] creyes|5 years ago|reply
[+] [-] ci5er|5 years ago|reply
Flipping through, I think the thyrister treatment is a bit weak, and I would ideally like to see more in terms of comm-sys, (like how NTSC works for analog/radio TV), but this looks solid.
TIL about a nice reference.
Thank you!
[+] [-] etrautmann|5 years ago|reply
[+] [-] mjoin|5 years ago|reply
[+] [-] lifeisstillgood|5 years ago|reply
[+] [-] Kim_Bruning|5 years ago|reply
Still somewhat surprising to me, this kind of simulation actually does help. It turns out that you actually do pick up a lot of intuitive feel that can serve well in an industrial context. I guess no matter how much theory you study on, it's still really insightful to just blow up some circuits. ;-)
Note that Electrical age currently works with older versions of minecraft (1.7) , though a rewrite is in the works.
https://electrical-age.net/
[+] [-] samstave|5 years ago|reply
(Many fail and are put off to learning the subject whenthere is no person they personally know to guide them through speed bumps)
[+] [-] HankB99|5 years ago|reply
My biggest issue is how to depict this in a format that I can share over Skype without putting in 80 hours of work. I might go with a series of pencil drawings and scan them in.
Are any of the suggested materials particularly suitable for this kind of presentation? This is intended to be a 20 minute or so presentation so I'm really just providing highlights. Points I want to get across include:
- Resistance anywhere in the circuit will cause problems. (e.g. bad ground connection.)
- Bad starting can be the result of a insufficient battery charge.
- Bad starting can be the result of high battery internal resistance.
- Bad starting can be the result of high resistance in the circuit.
- Operating with loads (e.g auxiliary lights and heated vest) that draw slightly more power than the charging system delivers can work for hours until the battery is discharged and the charging system no longer supports the loads. (DAMHIK!)
Thanks!
edit:formatting
[+] [-] jschwartzi|5 years ago|reply
I think it's very important to teach people that moving electric charges, represented by current, result in magnetic forces, and that these magnetic forces are what cause motors to turn. And an alternator or generator reverses the relation by spinning a magnetic field to generate current, which is why it charges a battery.
[+] [-] dataduck|5 years ago|reply
The pressure analogy is a really good one; the problem is a lot of people don't understand water pressure any better than they understand electricity.
[+] [-] vulcan01|5 years ago|reply
Or you could try streaming on Twitch (so that people can ask you questions as you explain stuff).
[+] [-] patterns|5 years ago|reply
[+] [-] VBprogrammer|5 years ago|reply
[+] [-] jpm_sd|5 years ago|reply
[+] [-] crks|5 years ago|reply
[0]: https://www.khanacademy.org/science/physics/electric-charge-...
[1]: https://www.khanacademy.org/science/physics/circuits-topic
[2]: https://www.khanacademy.org/science/electrical-engineering
[+] [-] steve_adams_86|5 years ago|reply
https://learn.sparkfun.com/tutorials/where-do-i-start/all
[+] [-] asd4|5 years ago|reply
Context: My biggest gripe with traditional education is lack of context for why a principle is important or useful. Not a problem when you are focused on a project.
Practicality: The practical aspects of theory are usually limited to core principles and help you see through the fog of all the details.
Narrative: Bringing many topics together in a project narrative give a linear path through the related principles which is less overwhelming.
https://hackaday.com articles, in my experience, have been a good jumping off point and often have solid links for better understanding.
A weakness of this approach is that it ignores the mathematical techniques to solving some of the problems. I doubt you will learn how to analyze circuits with differential equations or phasor analysis on a hobby site. That said, I rarely use these tools outside of an academic setting.
I'm sure someone will recommend The Art of Electronics. Its a great resource once you have the basics under your belt, but hard to use as a learning tool without prior knowledge. It touches on a lot of details by presenting a circuit and summarizing key points about its operation.
Once you have a handle on the basics I highly recommend playing with some circuits in a simulator. LTSpice is free and very high quality. There are other online options too.
You can experiment on hardware relatively safely if you stay away from high voltages and currents (avoid mains power and car batteries, always use circuit protection such as fuses). You will be frustrated if you have no test equipment though, a multimeter is a must-have.
[+] [-] bonzini|5 years ago|reply
[+] [-] lmilcin|5 years ago|reply
The difference is like being physicist and mechanic. Do you want to be physicist and understand electricity as a phenomena or do you want to be an engineer and use it for something useful. Believe me, there is less overlap than you think.
One good resource I have found is series of articles on http://amasci.com/ele-edu.html which mixes a little bit of both worlds.
Have fun!
[+] [-] pjc50|5 years ago|reply
How comfortable are you with "lies for children" oversimplifications of things that are extremely complicated but mostly irrelevant except in edge cases? (This phrase sounds perjorative but isn't, most of the time you don't need the complicated version and it actively impairs understanding what's going on. But it can be the only way to properly answer some questions like "what is electricity?")
I've occasionally considered writing my own, based on answering questions at electronics stackexchange, e.g. https://electronics.stackexchange.com/questions/245610/is-vo... / https://electronics.stackexchange.com/questions/272694/how-d... ; probably I would target explaining how the electron is a big source of "lies to children", and mostly an irrelevant distraction for beginner/intermediate work.
If you want a large book, The Art Of Electronics is the undisputed classic.
[+] [-] henrikeh|5 years ago|reply
[+] [-] 0culus|5 years ago|reply
[+] [-] yesenadam|5 years ago|reply
Articles on Electricity http://amasci.com/ele-edu.html
Great essays on understanding electricity, current, voltage, capacitors, transistors, batteries, static electricity etc etc, and popular misconceptions.
[+] [-] divbzero|5 years ago|reply
[1]: http://amasci.com/miscon/whatis.html
[2]: https://news.ycombinator.com/item?id=23442181
[+] [-] boruto|5 years ago|reply
There is also one about different types of plugs in Europe and UK which I cannot find
[+] [-] montroser|5 years ago|reply
One of my favorites: http://amasci.com/amateur/whygnd.html
[+] [-] aphextron|5 years ago|reply
[0] https://m.youtube.com/playlist?list=PLyQSN7X0ro2314mKyUiOILa...
[+] [-] morganvachon|5 years ago|reply
http://www.forrestmims.org/publications.html
[+] [-] gallamine|5 years ago|reply
[+] [-] kiliantics|5 years ago|reply
[+] [-] swiley|5 years ago|reply
[+] [-] ckmiller|5 years ago|reply
Just another resource that may help! You'll have no shortage of perspectives and approaches from the links here.
[+] [-] projektfu|5 years ago|reply
All of the water analogies were unhelpful for me. I did better just doing the math and seeing the result.
Someone else mentioned MITx. I did that and it was revolutionary. I also have a pretty good book called Practical Electronics for Inventors.
[+] [-] samjohnson|5 years ago|reply
This is a great observation. I've often thought that teaching Ohms law as I=V/R would lead to less confusion. Similarly, in intro physics why is mass acceleration introduced as f=ma? Wouldn't a=f/m have a clearer meaning?
[+] [-] projektfu|5 years ago|reply
[+] [-] beamatronic|5 years ago|reply
Same here, I just had to come to accept that there were orthogonal dimensions/measurements. It didn't matter if I understood them intuitively, as long as I worked with them orthogonally and in strict accordance with the basic equations.
[+] [-] soheilpro|5 years ago|reply
[+] [-] take_a_breath|5 years ago|reply
= For straight up electric concepts, I’d look at the Georgia Institute of Technology stuff on Coursera. “Introduction to Engineering Mechanics” and “Linear Circuits 1” were helpful.
[+] [-] tyingq|5 years ago|reply
https://www.fcctests.com/neets/Neets.htm
[+] [-] GlennS|5 years ago|reply
They've moved everything around since I did it, but I think this is the one: https://courses.edx.org/courses/course-v1:MITx+6.002x_6x+1T2...
[+] [-] observer4|5 years ago|reply
[Letters of a Radio-Engineer to His Son (1922)]((https://news.ycombinator.com/item?id=23358380)). It explains electricity without any technical jargon. Pretty nice first read. His atomic model is outdated, but that doesn't seem to interfere with anything. After reading the first initial letters, you might have a greater motivation to dive into more complicated texts.
[+] [-] TheHideout|5 years ago|reply