The preceding definitions may lead the reader into believing that there is no relationship between current, voltage and resistance. Nothing can be further from the truth. The relationship between current, voltage and resistance can be summed up by a statement known as Ohm's law. Voltage (E) is equal to amperage (I) times resistance (R): E=I x R Other forms of the formula are R=E/I and I=E/R
In each of these formulas, E is the voltage in volts, I is the current in amps and R is the resistance in ohms. The basic point to remember is that as the resistance of a circuit goes up, the amount of current that flows in the circuit will go down, if voltage remains the same.