Demonstrate that at the boundary between two media the normal components of the Poynting vector are continuous, i.e. S_(1n) = S_(1n).

Demonstrate that at the boundary between two media the normal componen

1.	Demonstrate that at the boundary between two media the normal components of the Poynting vector are continuous, i.e. S_(1n) = S_(1n).
Answer» Solution :Let `oversetrarr(N)` be along the `z` axis. Then `S_(In) = E_(1x) H_(1Y)-E_(1y)H_(1x)` and `S_(2n) = E_(2X)H_(2y) - E_(2y)H_(2x)` Using the bounadary condition `E_(1t) = E_(2T), H_(1t) H_(2t)` at the BOUNDARY `(t = x` or `y `) we see that `S_(1n) = S_(2n)`.

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Demonstrate that at the boundary between two media the normal components of the Poynting vector are continuous, i.e. S_(1n) = S_(1n).

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