Ohm's law calculator
Leave the unknown blank. Enter the other two. This is V = IR for a resistive element, not an AC impedance solve.
Method
V = IR. Power = VI. Worked case: 230 V across 46 Ω draws 5 A and dissipates 1,150 W.
Do not use this for cable sizing, motor starting or anything with reactance.
Logic: how this figure is built.
Last checked 2 October 2026. Worked figures are scenarios. See methodology and the disclaimer.