Historical Background

Ohm's Law was first published in 1827 by German physicist Georg Ohm. His experiments showed that the amount of electric current through a metal conductor in a circuit is directly proportional to the voltage impressed across it, for any given temperature.

Limitations of Ohm's Law

Ohm's Law applies to electrical circuits with constant resistance. It does not apply to non-ohmic devices like diodes and transistors, where the resistance varies with current and voltage. Temperature changes can also affect resistance and thus the application of Ohm's Law.

Practical Applications

Ohm's Law is fundamental in electrical engineering and is used in:

• Circuit design and analysis
• Power supply design
• Troubleshooting electrical problems
• Calculating power consumption
• Sizing electrical wires and components

Ohm's Law Triangle

The Ohm's Law triangle is a memory aid that helps remember the relationships between voltage (V), current (I), and resistance (R). By covering the quantity you want to calculate, the positions of the remaining quantities show how to calculate it.