Electronics/Ohm's Law

Electronics | Foreword | Basic Electronics | Complex Electronics | Electricity | Machines | History of Electronics | Appendix | edit

Ohm's law describes the relationship between voltage, current, and resistance.

Voltage and current are related such that voltage is equal to current times resistance:

Common units used in electronics calculations are:

V = mA × kΩ

Ohms law voltage source.svg

the current going through any point in the circuit, I, will be equal to the voltage V divided by the resistance R.

Ohms law current source.svg

In this example, the voltage across the resistor, V, will be equal to the supplied current, I, times the resistance R.


V=I times R
I=V divided by R
R=V divided by I