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A comment on Ask HN: What are some good resources to learn how electricity works?. Parent comment

Re:Ask HN: What are some good resources to learn how electri... by samjohnson on Thursday June 18, 2020 @09:46AM (#23563036)
> 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?

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Re:Ask HN: What are some good resources to learn how electri... by senderista on Thursday June 18, 2020 @10:46AM (#23563545)
I agree, that’s my preferred form as well. That’s because Ohm’s law is an empirical law, which states that current is proportional to voltage. It’s the definition of resistance, and it’s not always valid.
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Re:Ask HN: What are some good resources to learn how electri... by thehappypm on Thursday June 18, 2020 @09:57AM (#23563136)
Division is hard!
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Re:Ask HN: What are some good resources to learn how electri... by aphextron on Thursday June 18, 2020 @10:11AM (#23563271)
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".
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Re:Ask HN: What are some good resources to learn how electri... by tarlinian on Thursday June 18, 2020 @11:29AM (#23563984)
It also is infinitely more clear and simple to understand when you correctly realize that "F equals M times A" instead. I assume this was just an accidental transposition and you're not actually a crackpot. :)
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Re:Ask HN: What are some good resources to learn how electri... by aphextron on Thursday June 18, 2020 @11:57AM (#23564323)
Doh!
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