Ohm's Law
Ohm's law give de relations between Voltage, Resistance and Current in pure resistive circuit through two points.
Voltage and currente cannot be observed directly are often difficult to understand. To clarify these terms, some people make Electronic-hydraulic analogy sometimes called drain-pipe theory, the comparison between electrical circuits and water flowing in pipes. Here is a chart of the three electrical units (volt, Ampere, Ohm).
| Electrical | Description | Unit | Water Analogy |
|---|---|---|---|
| Resistance | Measure how difficult it is for current flow in a circuit | Ohm (Ω) |
Measure how diffilcult it is for water flow through a pipe |
| Current | Measure the flow of charge in a circuit. | Ampere (A) |
Amount of water flowing |
| Voltage or Potential Difference |
Measure of the Energy difference per unit charge between two points in a circuit. | Volt (V) | Water Pressure |
Formula
Elements
- I : Current, Ampere ( A )
- R : Resistance, Ohm ( Ω )
- V : Voltage, Volt ( V )
Examples:
V=50 Volts
I=2 Amps
Resistor=?
R=V/I=50/2=25Ω
Ohm's Law Calculator
Ohm's Law Simulator