Plane wave onto a planar interface

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Homework Statement



A plane wave is normally incident on tthe planar interface with a medium of refractive index n but the interface moves, in the same direction as the incident wave, at speed u. If the incident wave's frequency is OMEGAo, what are the frequencies OMEGA1, OMEGA2 of the reflected and transmitted waves respectively?


Homework Equations



I believe these are the equations. incident wave: exp[j(omega*t-k1n*r)] in region 1
reflected wave: exp[(j(omega*t+k1n*r)] in region 1
transmitted wave:exp[(j(omega*t-k2n*r)] in region 2
The wave function at each point z is given by f(t-z/c).

k1=omega*sqareroot(mu1*epsilon1) and k2=omega*sqarereoot(mu2*epsilon2)

NOTE:* in the exponential=means the those are two vectors dotted with each other

The Attempt at a Solution




I tried using the incident wave formula and trying to find what k was by making k=2*Pi/Lambda, but I got stuck and didn't know what lambda was. I also tried using f(t-u*t/c) and making it equal to sin(omega*t). I'm not sure if that's corrrect. I'm lost and I really need someone's help because I have submit this assignment by tomorrow morning at 9 a.m.!
 
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Is there a frame of reference that would simplify this problem?
 
Hi well the only thing I have to work with actually is the wave function at each point z is given by f(t-z/c). Therefore in the problem I made f(t-ut/c) equaled to sin(OMEGA0*t) and I went on from there.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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