It describes the magnetic fields that result from a transmitter wire or loop in electromagnetic surveys. Amperes circuital law states that maxwells observation. I know that many books in electromagnetics just post the maxwells equations in beginning claiming this is how it is. I first learned electromagnetics from griffiths text, and he doesnt. Eric hill, university of redlands, ca the physics teacher. Introduction a useful law that relates the net magnetic field along a closed loop to the electric current passing through the loop. Chapter maxwells equations and electromagnetic waves. Conduction current i and the displacement current id together possess the property of continuity along any closed path. The biotsavart law requires summing many infinitesimal current elements and thus allows for the direct calculation of any configuration of magnetic field due to currentcarrying wires. Applying these give you the amperemaxwells equation in matter. Ampere was a scientist experimenting with forces on wires carrying electric current. For steady currents, it is key for describing the magnetometric resistivity experiment. Suppose that is a short straightline element of this loop. Definition the integral around a closed path of the component of the magnetic field tangent to the.