In 1828, George Simon Ohm, a German physicist, found that for many substances, the electrical current I flowing through them is proportional to the voltage V across their ends.
The empirical relationship
V µ I
is called Ohm's Law. The constant of proportionality, called the resistance and given the symbol R, is independent of V or I, but depends only on the substances and its shape and size. Thus Ohm's Law is
V = R * I
Unit of Resistance:-
Volt per ampere OR Ohm ( W )
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