- #1

EmilyRuck

- 136

- 6

When considering the boundary conditions for the electromagnetic field [itex]\mathbf{E}, \mathbf{H}[/itex] on the surface of a Perfect Eletric Conductor we have:

- [itex]\mathbf{E} \times \mathbf{\hat{n}} = 0[/itex]
- [itex]\mathbf{J}_S = \mathbf{\hat{n}} \times \mathbf{H}[/itex]

The current density flows on the surface a PEC, so we can consider as an equivalent situation the superposition of [itex]\mathbf{J}_S[/itex] and its

*image current*, which is exactly opposite of [itex]\mathbf{J}_S[/itex]: the net current is 0 (this argument is used in order to prove that an electric current flowing on a PEC does not radiate).

But doesn't this affect the boundary conditions on the magnetic field? If the current is zero, why the relative boundary condition is not written as [itex]0 = \mathbf{\hat{n}} \times \mathbf{H}[/itex]?!

Emily