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Ohm's Law

Author: E.E. Kimberly

If a constant difference of potential V be impressed between the ends of a conductor, the current which will flow will be directly proportional to the difference of potential and inversely proportional to the resistance of the conductor. That fact was discovered by Ohm and the law bears his name. The relation may be expressed by the following formulas:

I = V/R


R = V/I


V = I*R



I = the current, in amperes;
R = the resistance, in ohms;
V = difference of potential, in volts.

Thus, the resistance of a conductor appears as a ratio of the difference of potential to the current which flows.

Last Update: 2010-11-22