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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
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Stay with low power. (Low tension and low intensity.)
How? Use batteries only? Obviously I shouldn't plug my own creations directly into the wall. Is it safe to use a low voltage "power brick"? Will any do, or do I need an especially robust one just in case?
Keep in mind though, that while these voltages are generally below the threshold required to conduct through skin, and represent little shock hazard, pretty much any electrical system can be hazardous in other ways.
In particular, you can create a fire hazard even with pretty low voltages, if the resistance is low enough and your power supply is capable of providing enough current. Likewise for sparks: if, FSM forbid, you happen to have some explosive vapors around (and even a bottle of fingernail polish remover can be a source of explosive vapors), a small spark can start a fire.
My point isn't to try to scare you off, but rather to say that you always need to be cautious, pay attention to what you're doing, and keep safety in mind, even when playing with low voltages.
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 calle…
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.
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As a kid I played with batteries and wall bricks or wall warts or whatever you call them(transformers). I would not say you need an especially robust one. They come in different sizes based on the amount of voltage they output and the potential current they can supply. Basically if you are playing with a 9 volt battery and want to replace it with a transformer just look for one that says 9v DC output on it.
There are people who say things like its not the voltage that kills its the current but through the human body under normal conditions it takes a decent bit of voltage to induce enough current to really hurt you. Watch out for things with large capacitors and large voltages. If you want to take something like that a part let it sit for a long time for the capacitors to discharge. I worked at a TV repair shop in high…
Oh man I have some retrocomputing equipment I really want to play with but I'm a little worried as there's a huge capacitor, some of the wires coming off the power supply manual are visibly old and to add to it, one of the first pages in the maintenance manual is a CPR guide.
I highly recommend the All About Circuits textbook: https://www.allaboutcircuits.com/textbook/ It starts from the very basics and builds up to quite complex circuits and their workings. It's an all-round great website, too.
I highly recommended "Every Circuit" it's a fun little electronics simulator which helps you to understand different electrical components and their interactions https://play.google.com/store/apps/details?id=com.everycircu...
The default example here is the LCR-circuit which to understand mathematically requires a bit of work https://en.wikipedia.org/wiki/RLC_circuit
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Division is hard!
It becomes infinitely more clear and simple to understand when you stop thinking in terms of "A equals F divided by M" and think of it as "A equals the ratio of F to M".
The ARRL Handbook for Radio Amateurs explains electricity and electronics for the beginner, and you might also get an interesting introduction to radio, too.
I highly recommend the All About Circuits textbook: https://www.allaboutcircuits.com/textbook/ It starts from the very basics and builds up to quite complex circuits and their workings. It's an all-round great website, too.
The Art of Electronics is also fantastic
It may be a great book for those who already have some grounding in the topic.