Ohm's Law & Power Calculator
Calculate power, voltage, current, or resistance.
Enter any two values
Calculated Power
24.00
Watts
The Relationship Between Power, Voltage, and Current
Electric power (P) is the rate at which electrical energy is transferred by an electric circuit. The relationship between power, voltage (V), current (I), and resistance (R) is described by both Ohm's Law and the Power Formula.
- Power Formula: `P = V × I` (Power = Voltage × Current)
- From Ohm's Law (V = I × R): We can derive two other power formulas: `P = I² × R` and `P = V² / R`.
This calculator uses these fundamental relationships. By providing any two of the four values (voltage, current, resistance), it can calculate the resulting power dissipation in Watts.
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