Ohm's Law
Compute V, I, R, or P from any two known values.
Example
You enter
- Voltage (V) 120
- Current (A) 10
You get
- Resistance 12.00 ohm
- Power 1,200.00 W
Checked against published worked examples from: Naval Education and Training Professional Development and Technology Center (US Navy).
Details, formula, and sources
Formula or tableOhm's Law: V = I * R; P = V * I. Derived identities for the missing two from any pair.
Source and editionClassical electromagnetism; physical fact. Identities verified against IEEE 141 (Red Book).
Free accessNo code citation required (physical fact). Reference texts free at archive.org and university OCW.
What governsEstimate. AHJ and licensed electrician govern. Verify against the NEC edition adopted in your jurisdiction.
API field namesV, I, R, P
- DC or RMS AC values are DC or RMS-equivalent ACconvention