Remembering OHM's Law

[daverj]

I made this graphic for somebody today, and figured there would be others here that could benefit from it.

It's easy to remember Ohm's Law and the Power Law using a simple triangular graphic. If you've had trouble remembering it in the past, try saving this image and printing out a copy to stick above your work bench.

[vozs]

[daverj]

Those might be useful to have on a wall, but unlike the triangle graphic they're not something that you can remember easily. The triangles are easy to remember and be able to recall the formulas when the graphic isn't right in front of you.

[Navs]

Thanks for this and all your help, Dave.

[mechie]

By doing a bit of substitution, these two triangles can produce a lot more formulas.

The second triangle shows that P = I*V
but if I don't know V?
The first triangle shows that V = I*R
If I make another triangle (as below), it can be seen that P = I*I*R
I*I is I(squared) so P = I(squared)*R

All the terms in each triangle can be treated just the same.
[/img]

[L-1]

I never seen nothing better about Ohm law than this picture:

[fonik]

:ROTFL:

[craque]

not certain but i am pretty sure that's a forrest mims drawing!

I never seen nothing better about Ohm law than this picture:

[iopop]

daverj: Your posts here are stellar, Thanks!

I hope someone with better english and editorial skills than I would compile all those posts - would be a great compendium on SDIY.

[J3RK]

daverj: Your posts here are stellar, Thanks!

I hope someone with better english and editorial skills than I would compile all those posts - would be a great compendium on SDIY.

Agreed! I know Dave has refined my understanding of many things on here. There have been numerous times where I had a minimal or spotty understanding of something until reading one of his posts.

Dr. Sketch n Etch, Ian Fritz, and Tim Stinchcombe too! (and others, but these spring to mind)

(oh, and that sketch of the Ohm's Law characters is one of my favorites too!)

[Thonk Support]

yeah that one really helps

I never seen nothing better about Ohm law than this picture:

[frijitz]

I never seen nothing better about Ohm law than this picture:

I agree. It emphasizes how things work rather than than rote memory of formulas. As voltage increases, current also increases, and as resistance increases current decreases. So the formula must be I = V/R. Also, power increases as either voltage or current increases, so it must be P = VI. All the other formulas are trivial algebraic variants.

Ian

[bazrush]

I made this graphic for somebody today, and figured there would be others here that could benefit from it.

Cool!

That arrangement was known as the VIR tree (a play on fir I presume) when I was learning electronics.

[source66]

Yes, cool!

[wsy]

Just remember the nursery rhyme!

Twinkle, twinkle, little star!
Power equals I squared R.

[wavecircle]

It's a good graphic but there's nothing about it being a metallic conductor at constant temperature.

[negativspace]

It's implied.

[russma]

I was taught that "E" is the signifier for voltage. Has that gone out of style, or is my memory worse than ever?


(trick question; my memory is worse than ever regardless of voltage)

[mechie]

I was taught that "E" is the signifier for voltage. Has that gone out of style, or is my memory worse than ever?

E = M * C squared doesn't it?

edit:
My mistake, I just checked up and found 'E' as I remember it from 40 years ago
E Pluribus

[daverj]

I was taught that "E" is the signifier for voltage. Has that gone out of style, or is my memory worse than ever?


(trick question; my memory is worse than ever regardless of voltage)

Me too. And the triangle I learned on had E at the top instead of V. But these days it seems to have gone out of style and V seems to be the common term used. So that's what I used in the graphics.

[decaying.sine]

Great figures! +1 on how much I have learned from reading posts from those fellas. It's kind of cool to see how your knowledge develops over time and you start "thinking" different and taking on new challenges. Good stuff.