The electrical resistance of a circuit component or device is defined as the ratio of the voltage applied to the electric current whichflows through it: If the resistance is constant over a considerable range of voltage, then Ohm's law, I = V/R, can be used to predict the behavior of the material. read more
Resistance of a resistor The function of a resistor is to oppose the electric current through it. This is called electrical resistance, and is measured in the unit ohm. read more