Ampere's law
In physics,
Ampère's law is the magnetic equivalent of
Gauss's law. It was discovered by
AndréMarie Ampère
It describes the relation between a circulating
magnetic field in a closed loop and the generated
electric current:

where
 B is the magnetic flux
 s is an infinitesimal element of the closed loop S
 I is the current encircled by the curve S
 μ_{0} is the permeability of free space
 is the path integral along the loop S
This law, as the others laws of
electromagnetism was later incorperated into
Maxwell's equations, unifying all of electromagnetism.