How Do Electromagnetic Waves Behave During Refraction?

AI Thread Summary
Electromagnetic waves behave differently during refraction based on their interaction with matter. When these waves collide with particles, they can be absorbed and reemitted, which slows them down, especially in denser materials. If the frequency of the electromagnetic wave matches that of the vibrating electrons in the material, the wave passes through without absorption, maintaining its speed and direction. Conversely, if the frequencies differ, the wave is absorbed and reemitted, altering its path and speed. Understanding these principles is crucial for effectively presenting the science fair project on refraction.
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I am doing a science fair project on refraction and I am preparing for the regionals and I found a small flaw in my report and I am wondering if any of you guys can help me out here.

This is what I wrote:

Why do electromagnetic waves warp when it goes through the process of refraction? The reason lies in the subatomic level of science. First of all, an electromagnetic wave is produced by a vibrating electric charge. As it traverses through a vacuum of space, it travels in a velocity of 2.99792458 x 108 m/s, or can be expressed as “c”. When the wave collides with a particle of matter, the wave is absorbed and the electrons within the atoms undergo a vibrating motion. If the frequency of the electromagnetic wave is not identical to the frequency of the vibrating electron, the energy is reemitted in a form prior to absorption, as an electromagnetic wave.
The new wave will have identical frequency as the previous wave and it will also travel through the trans-atomic space until it confronts another atom. If the frequencies are different, the electrons will go through a vibrating motion once again. This cycling process continues until the electromagnetic wave is transported through the medium.
This process is the fundamental cause of slowing down the velocity of an electromagnetic wave. Every photon in the electromagnetic wave travels the trans-atomic space at c, but the process of absorption slows it down. Therefore, the overall speed of an electromagnetic wave traversing any substance will have less speed as it would travel in a vacuum.



What I fear is, when the frequency between the EM wave is indeed identical to the frequency of the vibrating electron.. what happens then? I bet you 2 bottles of scotch that the judges will ask me that :biggrin:

Any assistance would be more than greatful.
Thank you very much :smile:
 
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I think where you went wrong is
When the wave collides with a particle of matter, the wave is absorbed and the electrons within the atoms undergo a vibrating motion. If the frequency of the electromagnetic wave is not identical to the frequency of the vibrating electron, the energy is reemitted in a form prior to absorption, as an electromagnetic wave.

Realize that the matter STARTS vibrating when the photon hits it. If the matter had really small density (like in space) then the light would not slow down at all, but if the matter does have a reasonable density, then the light will slow down more as density increases.

For example, the density of air is 1.2 kg/m^3 whereas the density of water is about 1000 kg/m^3. Thats why light travels much faster in air (2.8 x 10^8 m/s) than in water ( 2.2 x 10^8 m/s).
 


First of all, congratulations on your science fair project and good luck at regionals! It's great that you are already thinking ahead and anticipating potential questions from the judges.

To answer your question, when the frequency of the electromagnetic wave is identical to the frequency of the vibrating electron, the wave will not be absorbed and reemitted. Instead, the wave will pass through the material without any change in direction or speed. This is known as transparent materials, where the electromagnetic wave can easily pass through without any distortion.

However, if the frequency of the electromagnetic wave is not identical to the frequency of the vibrating electron, the wave will be absorbed and reemitted, causing the wave to change direction and slow down. This is known as opaque materials, where the electromagnetic wave cannot easily pass through and is instead absorbed by the material.

I hope this helps clarify any confusion and provides a solid explanation for your science fair project. Just remember to stay calm and confident during the presentation and be prepared to answer any additional questions from the judges. Good luck!
 
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