Absorption of EM wave

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Homework Statement


An electromagnetic wave is incident on a surface which absorbs all the electric field. Use Maxwell’s equations to determine the magnetic field on the other side of the surface.


Homework Equations



The Attempt at a Solution


My initial thought was that ##B=0## as a varying B field would produce an E field. But then I thought we could still have a constant E field that has no oscillations. Is this even possible (it doesn't seem likely to me).

Many thanks
 

Answers and Replies

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Delta2
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With the assumption that nothing "extraordinary" is happening on the other side of the surface (for example we could have another EM wave there or a static E-Field from a charge distribution), all you can deduce from Maxwell's equations is that:

-the magnetic field will be constant with respect to time . This follows from Faraday's law, you are right that the B field isn't necessarily zero but just constant wrt time(no time varying)

-the magnetic field will be curl-free (irrotational, or equivalently its curl will be zero) . This follows from Maxwell's-Ampere law, since we know that the E-field is zero on the other side
 

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