Law of electromagnetism that describes mathematically the magnetic force between two electric currents. It was named after A.-M. Ampère, who discovered that such forces exist. If two currents flow in the same direction, the force between the two...

In physics, Ampère's circuital law, discovered by André-Marie Ampère, relates the integrated magnetic field around a closed loop to the electric current passing through the loop. It is the magnetic analogue of Gauss's law, and one of the four...