Question

Find the angle of refraction if there is one. If there isn't, tell which substance reflects the light:

n=1.36
~~~~~~~~~~~Angle=15.60 degrees
n=1.73
~~~~~~~~~~~Angle=17.94 degrees
n=1.51
~~~~~~~~~~~Angle=27.71 degrees
n=1.0003
~~~~~~~~~~~Angle=11.08 degrees
n=2.42
~~~~~~~~~~~Angle=13.80 degrees
n=1.95

I solved for all of the angles using Snell's law, but I don't know how to tell if there's no angle of refraction and which substance would reflect the light.

Answer 1

There is no refraction angle (A2) if the sine of the computed angle (using Snell's law) is equal to or greater than 1.
N1 sin A1 = N2 sin A2
sin A2 = (N1/N2) sin A2 < 1
sin A2 < N2/N1;
otherwise there is only total internal reflection