Understanding Ohm's Law
Ohm's Law is one of the most fundamental principles in electrical engineering and physics. Named after German physicist Georg Simon Ohm, this law describes the relationship between voltage, current, and resistance in an electrical circuit.
The Basic Formula: V = I × R
The core of Ohm's Law states that voltage (V) equals current (I) multiplied by resistance (R). This simple relationship allows us to calculate any one of these three quantities when we know the other two.
Practical Applications
Ohm's Law is essential for designing electrical circuits and selecting appropriate components. Whether you're calculating the current through a resistor, determining the voltage drop across a component, or sizing wires for safe current carrying capacity, Ohm's Law provides the foundation for these calculations.
The Ohm's Law Wheel
The Ohm's Law wheel (or power wheel) combines Ohm's Law with the power formula to give 12 different equations for calculating voltage, current, resistance, and power. This tool allows you to find any value when you know any two of the four variables.
Limitations
Ohm's Law applies to linear, resistive circuits. It doesn't directly apply to components like capacitors and inductors, which have reactive properties. For AC circuits with these components, more complex calculations involving impedance are needed.