Relative Angles of light rays?

Question

The figure below shows a light ray passing from one material, to another, then to another. Considering the relative angles of the light rays in the figure, which of the following best describes the relative sizes of the indices of refraction?

http://i33.photobucket.com/albums/d77/alexsierra82/QUIZ1037PIC3.jpg

A) n2>n3>n1

B) n2>n1>n3

C) n3>n1>n2

D) n1>n2>n3

Consider a ray in a material of unknown index of refraction incident upon an interface with a material with an index of refraction of 1.07. You find that the critical angle is 46.71 degrees. What is the index of refraction of the first material?

Answer 1

B. Greatest angle to normal in 3, next greatest in 1, least in 2.

Critical angle = arcsin(n2/n1) where n2 is the lesser I.R.

n2 = 1.07; n1 = n2/sin(46.71 deg) = 1.47