htg
Full Member level 5
Consider a narrow EM wave beam propagating in the Z direction, whose intensity is maximal at the YZ plane and fades quickly as we move away from the YZ plane. Let X be the direction of the E vector.
Consider a small (w.r.t wavelength) cube, whose sides are parallel to the X,Y and Z axes, respectively. Let the cube be placed some distance away from the YZ plane. It seems that the flux of E through the closer face parallel to the YZ axis is bigger than the flux of E through the further face parallel to the YZ plane, in contradiction to the Gauss' law. What is the explanation?
(Even when we take it into account that the beam is divergent, we can still place the cube so that two of its facets are perpendicular to E. It still seems to contradict the Gauss' law).
Consider a small (w.r.t wavelength) cube, whose sides are parallel to the X,Y and Z axes, respectively. Let the cube be placed some distance away from the YZ plane. It seems that the flux of E through the closer face parallel to the YZ axis is bigger than the flux of E through the further face parallel to the YZ plane, in contradiction to the Gauss' law. What is the explanation?
(Even when we take it into account that the beam is divergent, we can still place the cube so that two of its facets are perpendicular to E. It still seems to contradict the Gauss' law).