Ohm's Law ...waves

Ohm's Law. The potential difference between any two pointsin a conductor is directly proportional to the current flowing throughit. (This only holds true for an ohmic material. Non-ohmic materialsdo not display a direct relationship.)V = IR
where V is the potential differencemeasured in volts, I is the currentmeasured in amperes and R is the resistance measured in ohms. Thus,1 ohm = 1 volt / ampere.The symbol used for the ohm is the Greek letter Omega(W).

Increased resistance in an electric circuit decreases conductance.Resistance and conductance are inversely related. The resistanceof a cylindrical resistor depends on its length, its cross-sectional area,its temperature and the resistivity of the material. Resistance is directlyproportional to the length of the conductor and varies inversely with its cross-sectional area. Resistance usually increases with temperature.Some materials exhibit superconductivity (i.e., resistance drops to zero)at lower temperatures. (Materials become superconductive at differenttemperatures.) Resistance depends on the resistivity of the material.The resistivity is defined as the resistance of a cylinder of the material1 meter long with a cross-sectional area of1 m². Resistivity varies withtemperature. It is measured inWm²/m.