The Definition of Ampere Is Confusing

Abstract

: SI unit of ampere is defined by means of magnetic force between two parallel conductors through which current flows. However, no mention is made of electric force in the opposite direction, which also exists between conductors. For that reason the existing definition is confusing for students, because it leads them to assume that by means of it ampere is also practically realized in laboratory. An analysis of forces shows that under certain conditions the electric force is much smaller than the magnetic force, but that fact still changes the physical picture of the propounded definition. The electric force can be compensated, which should be stated in textbooks when it comes to the definition of ampere, or else mention that ampere is practically realized by the current balance.