## ohm law Calculator tool

In the same circuit, the current in the conductor is proportional to the voltage at both ends of the conductor and inversely proportional to the conductor Resistance, which is ohm's law.

The formula R=U/I or U=IR derived from ohm's law I=U/R cannot say that the Resistance of a conductor is proportional to its voltage at both ends and inversely proportional to its current. Because the conductor Resistance is one kind of property of itself, it depends on the conductor length, cross-sectional area, material and temperature, humidity (the initial 2x2 section does not involve humidity), even if it has no voltage at both ends and no current through. Its Resistance value is also one fixed value. In general, this value can be regarded as constant, because the Resistance value is variable for the photosensitive Resistance and the thermal Resistance. For some conductors, there is also superconductivity at very low temperatures, which will affect the Resistance Resistance value and have to be considered.