Very complex question? The index of refraction for violet light in silica flint glass is 1.65....?

Question

The index of refraction for violet light in silica flint glass is 1.65 and that for red light is 1.62. What is the angle of deviation for the red ray passing through a prism of apex angle 58.2 degrees if the angle of incidence is 46 degrees?

What is the angular dispersion of visible light with the same angle of incidence?

Answer 1

The above solution has to be repeated again on the inside of
the prism just before the light comes out the other side.

The light gets refracted twice, one on contact with the prism, and
again before exiting the prism. So you have to calculate the
angle of incidence on the inside of the prism given the apex
angle of 46 and the refracted angle of 26.36. A geometry
problem. Then repeat above calculation.

Answer 2

I assume that the ray of light travels from the side of the prism and not the base (as most such experiments are carried out)

sin i/ sin r = n
sin 46/ sin r = 1.62
r = 26.36 (#)

sin i/ sin r = n
sin 46/ sin r = 1.65
r = 25.85

angular dispersion of visible light = 26.36 - 25.85 = 0.51 degress.

Hope its correct.