The voltage across a resistor can be considered as an indirect measure of the current flowing through the resistor. It is an effective way to determine how much current is flowing through a resistor without actually measuring it directly. We will take this idea further and use this concept to measure the flow of electrons in an electrochemical cell. This is the graph of the resistance of Ohmic resistor for different values of (Ri, i = 1, 2, 3). Non- Ohmic resistors (R4, light bulb) do not obey Ohm's Law.