Ohms Law Calculator
The complete Ohm's law solver. Pick which two values you know — voltage & current, voltage & resistance, or current & resistance — enter them, and get the missing quantity along with power dissipation and a step-by-step derivation of every relationship.
TheCalculators — Ohms Law Calculator
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Resistance (R)
6 Ω
Power dissipated: 24 W
- Voltage (V)
- 12 V
- Current (I)
- 2 A
- Resistance (R)
- 6 Ω
- Power (P)
- 24 W
- Check: I² × R
- 24 W
Step-by-step solution
- 1Solve for RR = V ÷ I
- 2SubstituteR = 12 ÷ 2 = 6 Ω
- 3PowerP = V × I = 12 × 2 = 24 W (equivalently I²R or V²/R)
Ohm's law & power wheel reference
Computed for DC or purely resistive AC loads. Reactive (inductive/capacitive) circuits need impedance, not plain resistance.
Most useful next
Formula
V = I × R · P = V × I = I² × R = V² ÷ R
Pro tips
- • A 60 W bulb on 120 V draws 0.5 A — I = P ÷ V.
- • Doubling voltage with fixed resistance doubles current and quadruples power.
FAQ
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