Alternative formulas for Ohms law

[brinker]

TL;DR

Ohms law, electricity

Hi.
Have any one try this way:
R=V2/P

 

[Averagesupernova]

Yes. Is it so strange to believe that wouldn't be a thing? If you know two of the three, you can find the third. Rearrange the equation if you like, basic algebra.

 

[DaveE]

TL;DR Summary: Ohms law, electricity

Hi.
Have any one try this way:
R=V2/P

Yes, all the time. This isn't exactly Ohm's law. He didn't include anything about power.

P=V²/R and P=I²R are equations that I used frequently.

All of the combinations of the basic definitions R=V/I and P=VI are useful. You'll need to get to the point where you can use simple algebra to manipulate these to find what you want from the data you have.

 

[berkeman]

Have any one try this way:
R=V2/P

Lordy. I'm glad @Averagesupernova and @DaveE understood your question as written; I sure did not.

@brinker -- I will send you some tips on using LaTeX to post math equations at PF. In the mean time, please be sure to show exponentiation using the "^" symbol. When I read your equation as written, I could not figure out where the variable $V_2$ came from and what in the world the variable $P$ was. Now that I've seen the replies talking about the power equation, I realize that what you meant to write was R=V^2/P, or in LaTeX:
$$R = \frac{V^2}{P}$$

 

[sophiecentaur]

Yes, all the time. This isn't exactly Ohm's law. He didn't include anything about power.

And, of course, Ohm's Law is not being quoted here completely. Ohm's law deals only with metals at a constant temperature. The algebra is correct only under these conditions where the effective resistance of a component is constant. The equation is not valid for diodes or filament light bulbs etc..