Why does total internal reflection happen in glass?
What determines whether total internal reflection can occur?
any microscopic answer?
Perhaps these will help. I pulled them off a Google search:
If you go back to Maxwell's equations for the propagation of electromagnetic radiation (E cross H) in media and at surfaces, you will find that there are certain cases where light will be entirely internally reflected. Also, you will find from Maxwell's equations that at a specific angle of incidence on water or glass, one polarization is entirely refracted, and the other completely reflected (Brewster's angle). (Why do fishermen wear polarizing sunglasses?)
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