Ohm's Law
Ohm's law is an empirical law relating the voltage V across an element to the current I through it:
(V is directly proportional to I). This law is not always true: For example, it is false for diodes, batteries, etc. However, it is true to a very good approximation for wires and resistors (assuming that other conditions, including temperature, are held fixed). Materials or objects where Ohm's law is true are called "ohmic".
For ohmic materials, the resistance R and conductance G are defined by:
Therefore, resistance and conductance are inverses:
Read more about this topic: Electrical Resistance And Conductance
Famous quotes containing the word law:
“The law of nature is alternation for evermore. Each electrical state superinduces the opposite. The soul environs itself with friends, that it may enter into a grander self-acquaintance or solitude; and it goes alone for a season, that it may exalt its conversation or society.”
—Ralph Waldo Emerson (1803–1882)