(adsbygoogle = window.adsbygoogle || []).push({}); A "unit magnitude" EM Wave?

1. The problem statement, all variables and given/known data

Write down the solution of Maxwell's equations corresponding to a plane polarised EM wave of unit amplitude and wavelength λ=2∏m, polarised in the zy plane and travelling in vacuo in the minus y direction.

2. Relevant equations

∇.E = 0

∇.B = 0

∇xE = -dB/dt

∇xB = με(dE/dt)

(they're meant to have subscript noughts...)

3. The attempt at a solution

Ok, so polarised in zy plane means E in z direction, B in x direction. λ=2∏m, combined with the fact that the speed is c, gives (1/m(y+ct)) as the argument.

So I haveE=zcos(1/m(y+ct)) andb=x(1/c)cos(1/m(y+ct))

(z and x meant to be unit vectors) since there has to be a factor 1/c between their amplitudes...

Now this is probably a really stupid question, but what exactly does "unit amplitude" mean? Because, I mean, there are two waves - E and B. And if E has unit amplitude then B has amplitude 1/c...

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# Homework Help: A unit magnitude EM Wave?

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