⚡ Ohm's Law Calculator
Calculate voltage, current, resistance, and power
📏 Enter Any Two Values
📊 Calculated Values
Voltage (V)
Current (A)
Resistance (Ω)
Power (W)
📚 Understanding Ohm's Law
What is Ohm's Law?
Ohm's Law describes the relationship between voltage, current, and resistance in an electrical circuit. It states that the current through a conductor is directly proportional to the voltage across it and inversely proportional to its resistance.
Formulas
- V = I × R (Voltage = Current × Resistance)
- I = V / R (Current = Voltage / Resistance)
- R = V / I (Resistance = Voltage / Current)
- P = V × I (Power = Voltage × Current)
- P = I² × R (Power = Current² × Resistance)
- P = V² / R (Power = Voltage² / Resistance)
Units
- Voltage (V): Volts - The electrical potential difference
- Current (I): Amperes (Amps) - The flow of electric charge
- Resistance (R): Ohms (Ω) - Opposition to current flow
- Power (P): Watts - Rate of energy transfer
Frequently Asked Questions
What is Ohm's Law used for?
Ohm's Law is fundamental in electrical engineering and electronics. It's used to calculate voltage, current, or resistance in circuits, design electrical systems, troubleshoot circuit problems, and determine power consumption.
How do I calculate voltage using Ohm's Law?
To calculate voltage, multiply current by resistance: V = I × R. For example, if current is 2A and resistance is 10Ω, then voltage is 2 × 10 = 20V.
What happens if resistance increases?
If voltage remains constant and resistance increases, current decreases proportionally (I = V / R). This is why resistors are used to limit current in circuits.