Interactive Ohm's Law Calculator

Voltage (V): volts [V]

Current (I): amperes [A]

Resistance (R): ohms [Ω]

Power (P): watts [W]

Formulas used will appear here...

Learning Coach

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Ohm's Law & Power Formulas

Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points. It is expressed as V = I × R.

Electrical power (P) is the rate at which electrical energy is transferred. In resistive circuits, it can be calculated using Joule's Law combined with Ohm's Law, leading to formulas like P = V × I, P = I² × R, and P = V² / R.