Ranking materials in order of their refraction index.

[vf_one]

Hi everyone

I'm having a bit of trouble solving this question. If anyone can help that would be awesome

Homework Statement
Rank the materials in the diagram according to their refractive indices from greatest to smallest (see attachment)

The attempt at a solution
The greater the refractive index of a material, the slower the wave will travel and therefore the more it will bend towards the normal.

From the diagram, the angle of refraction in medium C is smaller than the angle of incidence in medium A so n_C > n_A

The angle of incidence in medium C is smaller than the angle of refraction in medium B so n_C > n_B

the wave seems to travel a lot faster in medium B than A as it bends further away from the normal so n_A>n_B

So n_C > n_A > n_B

But the answer is n_A > n_C > n_B

Why is n_A > n_C??

 

[ehild]

Both the angle of incidence and the angle of refraction are measured from the normal of the surface.

ehild