Exact electromagnetic fields produced by a finite wire with constant current

摘要

We solve exactly the problem of calculating the electromagnetic fields produced by a finite wire with a constant current, by using two methods: retarded potentials and Jefimenko's formalism. One result in this particular case is that the usual Biot - Savart law of magnetostatics gives the correct magnetic field of the problem. We also show graphically the corresponding Poynting vector.