If the angle of incidence is zero, can you have Total Internal reflection?

Question

I was just wondering, when studying for my electromagnetism exam, if its possible to get TIR if the angle of incidence is zero degrees.

Answer 1

0 degrees from the normal, I would say yes because you could shine something onto a reflective surface.  It's not really based on snell's law, and I don't know if you would always have some transmittance, but I think it would work.

Answer 2

No, this is not possible.  There is always a region in which you get at least partial transmittance of the incident ray.

As the index of refraction of the material approaches infinity, the angle inside which transmittance occurs approaches zero, but the speed of light in the material also approaches zero, so it's a moot point.