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Any two solve the other two.

Enter any two of voltage, current, resistance, or power — Ohm's law fills in the rest, with the formula it used.

VVoltage= calc
V
ICurrent= calc
A
RResistance= calc
Ω
PPower= calc
W
Enter any two values to solve the other two.

The Ohm's law & power wheel

V = I × RI = V ÷ RR = V ÷ IP = V × IP = I² × RP = V² ÷ R

For DC or resistive AC loads; real AC circuits also involve power factor, reactance, and phase. A learning and field-reference aid — verify against the NEC and your meter for live work.

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