Some questions about physics and light refraction/ bending?!?

Question

1) Is refraction of light a reversible process?

2) What happens to the wavelength of light as it passes from a more dense to a less dense medium?

3) If the angle of incidence from glass to air exceed the critical angle, what will happen?

4) How might the following professionals make use of Snell's Law?
a) Gemologist
b) food scientist
c) Environmental Protection Agency (EPA) Investigator

5) Every day life application for general concepts of refraction of light??

Much thanks! Just answer as many as you can :]

Answer 1

1)Yes, if u change the property of that medium, by adding glycerine in water, or... etc. then the angle of refration would reverse out... or depending what u want to attain...

2)The velocity increases, due to the fact that the WAVELENGTH increases.

3) There will be total reflection, no refraction above the glass will be seen

4) to get better shine / reflection in stone -
try to measure reflection off marine or other food (spoilage) -
EPA can do the same with GAs refration, eyc

5)Fiber Optics communication,, Electro-Optic modulators,, Wave Scattering phenomenon/research etc

Answer 2

1. In theory, you would need a substance with a negative index of refraction. There's been some research into this.

I'd have to bust old my old college books to remember the rest.

Answer 3

a decrease diamond acts as a prism, placing apart the white mild into the 7 colorations of the rainbow idk for the 2d one for the rainbow, it has to handle the wavelengths of the guy colorations of light in the mild being refracted with the help of the prism. pink mild has the longest wavelength, so it appears that evidently on correct, while blue mild has the shortest, so its on bottom. colorations in route of pink have an prolonged wavelength, and those in route of blue have a shorter one