- Joined
- May 13, 2009
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Hey guys, so I learned that lightwaves do NOT change in energy or frequency when they cross new mediums. They only change in wavelength and velocity.
Applying the theory n = c/v, it makes sense that the light travels slower in bigger n indexes. But why does it really? My original theory was that light waves would have to collide into the denser medium objects and have to randomly bounce around before coming out the other end... but this logic was cut short by a Kaplan test I just did earlier.
The kaplan test solution stated that the lightwaves travel slower in denser mediums because when the lightwaves collide with the atomic structures of the denser medium (with its electrons in orbit), they rise in energy, and then fall back down, thus emitting light back out... but with lower energy, since some of the energy was absorbed by the atom. This fall in energy would be the reason why the velocity fell.
This is the point I do not understand. I was told before by Kaplan that the frequency does not change when you cross new mediums for lightwaves. Yet they stated here that the energy decrease caused the decrease in velocity. If this was the case, E = hf, then frequency must have also decreased.
BLASPHEMY!!! Can somebody please explain this to me?? I would really like to clear this logic before my test which I'm writing in 1.5 days...
... also, as a side note, can somebody tell me if soundwaves would also remain unchanged in frequency when they cross into denser mediums? I know that their velocity increases (as opposed to light) when they cross into denser mediums.
Thank you!!
Applying the theory n = c/v, it makes sense that the light travels slower in bigger n indexes. But why does it really? My original theory was that light waves would have to collide into the denser medium objects and have to randomly bounce around before coming out the other end... but this logic was cut short by a Kaplan test I just did earlier.
The kaplan test solution stated that the lightwaves travel slower in denser mediums because when the lightwaves collide with the atomic structures of the denser medium (with its electrons in orbit), they rise in energy, and then fall back down, thus emitting light back out... but with lower energy, since some of the energy was absorbed by the atom. This fall in energy would be the reason why the velocity fell.
This is the point I do not understand. I was told before by Kaplan that the frequency does not change when you cross new mediums for lightwaves. Yet they stated here that the energy decrease caused the decrease in velocity. If this was the case, E = hf, then frequency must have also decreased.
BLASPHEMY!!! Can somebody please explain this to me?? I would really like to clear this logic before my test which I'm writing in 1.5 days...
... also, as a side note, can somebody tell me if soundwaves would also remain unchanged in frequency when they cross into denser mediums? I know that their velocity increases (as opposed to light) when they cross into denser mediums.
Thank you!!
