ABSTRACT
When an electromagnetic wave impinges on a sheet of metal, the electric eld component induces a current ow in the sheet. Some electromagnetic theories of shielding state that the current ow has a current density of 2Ho or 2Eo/Zw, whereas other electromagnetic theories state that the current is equal to Ho. Figure 6.1 shows the incident electromagnetic wave and the induced current, from which it can be seen that the magnetic intensity produced by the induced current is such as to annihilate the magnetic intensity behind the sheet and to double the intensity in front of the sheet, assuming a perfectly conducting innitely large sheet. A standing wave is generated in front of the sheet, and this can be seen in Figure 6.1.
