In the three tables to the right, you may enter two of the three factors in Ohm's (original) Law. They are Voltage (V) or (E), measured in Volts, Current or Amperage (I), measured in Amps (Amperes), and Resistance (R) measured in Ohms. The third factor will be calculated for you when you click on the Calculate button for that table.
Ohm's Law is V = I x R where V = Voltage, I = Current and R = Resistance. One ohm is the resistance value through which one volt will maintain a current of one ampere.
Georg Simon Ohm was the Bavarian physicist who determined the mathematical law of electric currents called Ohm's Law. The ohm, an electrical unit of resistance, was named for him. Between 1825 and 1827, he devised the theory or the relationships and it was credited to him in late 1827.