E = Em sin(kx-wt) and I = T+R what wavelength is reflected wave

[morrobay]

When a light wave enters a medium the electric field value of the wave is smaller in the medium.
With the incident wave = transmission wave + reflected wave. If the E field of the
reflected wave is known . Can the wavelength of the reflected wave be obtained from
these relationships :
E = Em sin (kx=wt)
k = 2 pi/wavelength
This question is related to this thread https://www.physicsforums.com/showthread.php?t=463293

 

[morrobay]

When a light wave enters a medium the electric field value of the wave is smaller in the medium.
With the incident wave = transmission wave + reflected wave. If the E field of the
reflected wave is known . Can the wavelength of the reflected wave be obtained from
these relationships :
E = Em sin (kx=wt)
k = 2 pi/wavelength
This question is related to this thread https://www.physicsforums.com/showthread.php?t=463293

If this question is stated correctly does it have an answer ?
If not stated correctly can someone restate w/correction
Asking if the electric field value of the reflected wave is known based on:
E reflected wave = E incident wave - E transmitted wave - E absorbed wave
Then can wavelength of reflected wave be obtained from above formulas.

 

[Antiphon]

The wavelength of the reflected wave is the same as the incident wave. Photon energy is not changed on reflection.