Solve EM Wave Vacuum Homework: Prove Relation, Find B, Reflect Wave Form

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Homework Statement


EM Waves propagating through vacuum towards the x-direction approaches a conducting surface at x = 0.

Part (a): Prove the following relations. Find the boundary conditions for E and B if charge density σ and current density s exists on the surface.

Part (b): Find B in terms of E_0

Part (c): Show the reflected wave has the following form:

Part (d) Find magnetic field of reflected wave and s

Homework Equations


The Attempt at a Solution



Part(a)
33xbj9w.png


Part(b)
migps3.png


Part(c)

This is the part that disturbs me. I assumed the free current s = 0 and σ = 0. Usually k would be perpendicular to the surface, making derivations easier.

I actually got perpendicular reflected E-field = 0, which is wrong..
But, I got parallel reflected E-field = - incoming parallel E-field, which is right

rms6rn.png


I'm confused - If it's a perfect conductor it should have no free charge or currents, but the question says it does. Then again, in order to derive the reflected e-field, we need to assume they are 0.
 
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Edit: Question here
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