Ohm's Law Calculator
Calculate voltage, current, or resistance using Ohm's Law.
Ohm's Law Calculator
Common Ohm's Law Scenarios
Click on these links to see instant calculations with common values:
Understanding Ohm's Law
Ohm's Law is a fundamental principle in electrical engineering that describes the relationship between voltage, current, and resistance in an electrical circuit.
Formulas
Current (I): I = V / R
Resistance (R): R = V / I
Where:
• V = Voltage in Volts
• I = Current in Amperes
• R = Resistance in Ohms
Key Concepts
- Voltage (V): The electric potential difference between two points, often thought of as the 'pressure' that pushes electrons.
- Current (I): The rate of flow of electric charge, measured in Amperes.
- Resistance (R): The opposition to the flow of electric current, measured in Ohms.
Typical Values in Ohm's Law
| Component/Circuit | Voltage (V) | Current (A) | Resistance (Ω) |
|---|---|---|---|
| LED (with resistor) | 3 | 0.02 | 150 |
| Small DC Motor | 12 | 0.5 | 24 |
| Incandescent Bulb | 120 | 0.83 | 144 |
| Heating Element | 240 | 10 | 24 |
| Standard Resistor | 5 | 0.005 | 1000 |
Frequently Asked Questions
What is the relationship between voltage, current, and resistance?
Ohm's Law defines this relationship: Voltage is directly proportional to current and resistance. This means if you increase voltage, current increases (given constant resistance), and if you increase resistance, current decreases (given constant voltage).
Can Ohm's Law be applied to AC circuits?
Yes, Ohm's Law can be applied to AC circuits, but it becomes more complex due to impedance (which includes resistance, inductive reactance, and capacitive reactance) and phase differences. For simple resistive AC circuits, V=IR still holds true.