Ohm's Law

Ohm's Law tells you how voltage, current, and resistance are linked in many simple electrical circuits. If the resistance stays the same, a bigger voltage pushes more current through the circuit; if resistance increases, less current can flow for the same voltage. The relationship comes from how easily charge carriers move through a material, so it is especially accurate for many metals and other ohmic components over a normal operating range.

Use this formula when you know any two of voltage, current, and resistance and need to find the third. It is common in circuit analysis, checking resistor values, and troubleshooting basic electronics.

• mixing up the units, especially using ohms or amps in the wrong place
• forgetting to rearrange the formula correctly when solving for I or R
• using Ohm's Law for components that do not behave like simple resistors