Ohm's Law Calculator
Calculate voltage, current, and resistance
Ohm's Law: V = I × R
V = Voltage (V), I = Current (A), R = Resistance (Ω), P = Power (W)
Ohm's Law
Ohm's law is a fundamental law in electrical engineering that describes the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. It was discovered by German physicist Georg Ohm in 1827. This law is essential for understanding how electrical circuits work.
V = I × R
Where: V = Voltage (Volt), I = Current (Ampere), R = Resistance (Ohm)
Derived Formulas
Calculate Current
I = V / R
Current is directly proportional to voltage and inversely proportional to resistance
Calculate Resistance
R = V / I
Resistance equals voltage divided by current
Calculate Power
P = V × I = I² × R = V² / R
Electrical power equals voltage multiplied by current
Practical Examples
Example: Light bulb
A light bulb connected to 120 volts with resistance of 240 ohms. Current = 120 / 240 = 0.5 amperes. Power = 120 × 0.5 = 60 watts.