Ohm's law states that the voltage within an electrical circuit is equal to the product of the current and the voltage. Mathematically it is written as V=IR where V is the voltage, I is the current and R is the resistance. If a circuit has a voltage of 9.0 Volts and a resistance of 36.0 Ohms, the current is I = V / R = 9.0/36.0 = 0.25 Amps.
