Refraction Question

[Medgen]

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So I came across the following question, and I have gone over and over it in my head and can't figure out how to reconcile it with my notion of chromatic dispersion:

"White light strikes a glass surface from air at an angle of 30 degrees. The light is split into colors in a phenomenon known as dispersion. What color light will have the greatest angle of refraction?"
A. Red
B. Yellow
C. Green
D. Blue

The explanation indicates that longer wavelengths will have a greater angle of refraction when light goes from a medium with a lower index of refraction to a medium with a higher index of refraction.

I feel like the answer should be blue because blue has the smallest wavelength and bends the most in chromatic dispersion. It bends the most because it has the lowest speed. How can blue have the smallest angle of refraction (largest n) and also bend the most?

Thanks!

 

[Medgen]

Not sure if this will be of use to anyone, but I figured it out and thought that I would post it.

Blue light refracts less than red light but bends in chromatic dispersion more than red light because it travels more slowly. So, the lower velocity contributes to both the greater bending and decreased refraction, when comparing it to other types of light.

 

[MT Headed]

I think you are confusing "angle of refraction" with "amount the light bent from the expected straight-line value".

The blue light bends the most. Towards the normal. Angle of refraction is measured from the normal. Therefore blue light also has the smallest angle of refraction.

 

[Medgen]

I think you are confusing "angle of refraction" with "amount the light bent from the expected straight-line value".

The blue light bends the most. Towards the normal. Angle of refraction is measured from the normal. Therefore blue light also has the smallest angle of refraction.

That makes sense now that I look at the diagram. Thanks! This was really bothering me yesterday.