The relationship between Voltage & Current
The Relationship Between Voltage & Current
Georg Simon Ohm discovered that the amount of current
that flows through a material is proportional to the potential
difference or voltage applied across it. His famous
law states that V = IR; if a certain voltage (V) is
applied across a conductor, the size of the current (I) which flows
is inversely proportional to the resistance (R) of the
conductor.
The Ampere
The SI base unit for electrical quantities is the ampere. The
definition of the ampere adopted in 1948, is: The ampere is that
constant current which, if maintained in two
straight parallel conductors of infinite length, of negligible
circular cross-section, and placed 1 meter apart in vacuum, would
produce between these conductors a force equal to 2 x 10- 7
newtons per meter of length.