Why is there total internal reflection

AI Thread Summary
Total internal reflection occurs when the angle of incidence exceeds the critical angle due to the refractive properties of the media involved, which prevent wave transmission. This phenomenon results in most of the incident energy being reflected back into the original medium, forming standing waves at the boundary. The refractive index, which influences this behavior, is determined by the electromagnetic properties of the materials, including their dielectric permittivity and magnetic permeability. The discussion also touches on how light interacts with different media, illustrating that the angle of incidence affects the energy transfer across boundaries. Understanding these principles is essential for exploring advanced topics like metamaterials and their unique properties.
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Why will total internal reflection occur when angle of incidence is greater than the critical angle? Anything deal with the particles?
 
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ppt said:
Why will total internal reflection occur when angle of incidence is greater than the critical angle? Anything deal with the particles?

Because the medias have such properties (resulting in certain refraction index), that there is no transmitted propagating wave. Some part of energy forms a standing wave parallel to the boundary surface in the incidence plane, but the major part is reflected back to the source media.
 
why do the medias have such properties?
 
why do the medias have such properties?

well, well, well... :))) (as they say: "es ist nich leicht ein gott zu sein")
who knows? we just observe the nature. it turns out that the properties are like that! However there exist some special investigations dealing with artificial medias (keywords: metamaterials, chirality, nonreciprocity) that are quite perspective...
now if ask what makes up the refraction index - n=sqrt(epsilon*miu) - (square root of relative diel. permittivity and magn. permeability product). So the refraction index depends on EM properties of the matter - what kind of electric or magnetic dipole moment do atoms possesses while interaction with the wave, surely their resonance properties and so on...

it's be better if you state the question more specifically ;)
 
Here is another way of thinking abt it; i pretty much made it up right now but it might help understand it better, p.s this is not to be taken too seriously, but it's an explanation that should suffice for now...

Think of it this way, light has a certain amt of energy given by E = hf. Right, now water is one medium and air is another and they are both horizontal, like a pool water on the bottom and air on the top, water has surface tension,

now light wanting to get out of it will have to go upward, so resolve vectorally, cos90 being zero and cos zero being 1... Therefore the light will have the greatest y-axis component when the light is at 90 and the least when light is at 0 i.e parallel to the surface of water... Therefore light will have least amt of problem getting through the surface tension of water at 0 degrees and the maximum problem of getting out of it 90 degrees... Therefore depending on the refractive indeces or the diffrence in pressure at the join of the two surfaces, we have a critical angle...

I hope this makes some sense...

Guyz please go easy on me...
 
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