Ohm’s Law is a relationship between the voltage, current and resistance of a resistor:
V = I R
where:
V = voltage across the resistor (in volts or V)
I = the current through the resistor (in amps or A)
R = the resistance of the resistor (in ohms or Ω).
The voltage across the resistor in the diagram at right is 12V. The current through the resistor is 6A. Solving Ohm’s Law for the resistance gives:
R = V/I.
Substituting gives:
R = (12V)/(6A) = 2Ω.