Ohm's Law Calculator
Calculate voltage, current, resistance, or power using Ohm's Law formulas. Enter any two known values to find the others.
Ohm's Law Parameters
Ohm's Law Formulas
Ohm's Law describes the relationship between voltage, current, and resistance. Power is also closely related.
Where:
- V = Voltage (Volts)
- I = Current (Amperes)
- R = Resistance (Ohms)
- P = Power (Watts)
Common Electrical Values
| Quantity | Typical Values | Description |
|---|---|---|
| Voltage (V) | 1.5V (AA battery), 12V (car battery), 120V/240V (household) | Electrical potential difference |
| Current (A) | 0.1A (LED), 1A (small motor), 15A (household circuit) | Flow of electric charge |
| Resistance (Ω) | 10Ω (small resistor), 100Ω (heating element), 1kΩ (sensor) | Opposition to current flow |
| Power (W) | 1W (small LED), 60W (light bulb), 1500W (microwave) | Rate of energy transfer |
Frequently Asked Questions
What is Ohm's Law?
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 commonly expressed as V = IR, where V is voltage, I is current, and R is resistance.
What are the units for Voltage, Current, Resistance, and Power?
Voltage (V) is measured in Volts, Current (I) in Amperes (Amps), Resistance (R) in Ohms, and Power (P) in Watts.
How is power related to Ohm's Law?
Power (P) can be calculated using variations of Ohm's Law: P = V * I (Voltage multiplied by Current), P = I² * R (Current squared multiplied by Resistance), or P = V² / R (Voltage squared divided by Resistance).