0steveastrouk 11 years ago It isn't the opposite ! You can define a unit called conductance, which is 1/resistance. It has the SI unit of the Siemen. 1000 Ohms is 1mOhm, 100 Ohms is 0.01 Siemens, 1 Ohm is 1 Siemen. If you want to imagine a potentiometer calibrated in Siemens instead, you have a variable conductance.