Dispersion and Refraction

[pm1]

I know there have been other posts but I'm still no quite sure if I got it down...

So from what I understood there a couple fundamental rules about waves:
1) frequency does not change when a wave is going from one medium to another.
2) the speed of the wave is determined by the medium (which makes sense, since frequency - as stated in #1 - is kept constant).

But, then there are exceptions to rule #2.
Although index of refraction seemed to be a value of a specific material (the ratio of c/v) it can actually change when dispersion happens. Dispersion is when a light is shine through a prism and different colors are separated/bent differently due to different velocity of each wave color.
Now that's when I start getting very confused..
From what I read the different bending degrees of each light color is dependent on that color's frequency. Apparently frequency determines the velocity of the color through a medium.
All the info I found states that red (lower frequency) will bent less due to its lower n, because it has lower velocity. How come is that true?
1. At first I thought.. well, red light does have a lower frequency but it also has a higher wavelength.. so shouldn't each factor compensate for the other? keeping v the same? Should we just take it as an exception?
2. If velocity is determined by frequency, shouldn't red have a lower velocity because v=lambda*f hence giving a bigger n?
😕

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[MrNeuro]

I know there have been other posts but I'm still no quite sure if I got it down...

So from what I understood there a couple fundamental rules about waves:
1) frequency does not change when a wave is going from one medium to another.
2) the speed of the wave is determined by the medium (which makes sense, since frequency - as stated in #1 - is kept constant).

But, then there are exceptions to rule #2.
Although index of refraction seemed to be a value of a specific material (the ratio of c/v) it can actually change when dispersion happens. Dispersion is when a light is shine through a prism and different colors are separated/bent differently due to different velocity of each wave color.
Now that's when I start getting very confused..
From what I read the different bending degrees of each light color is dependent on that color's frequency. Apparently frequency determines the velocity of the color through a medium.
All the info I found states that red (lower frequency) will bent less due to its lower n, because it has lower velocity. How come is that true?
1. At first I thought.. well, red light does have a lower frequency but it also has a higher wavelength.. so shouldn't each factor compensate for the other? keeping v the same? Should we just take it as an exception?
2. If velocity is determined by frequency, shouldn't red have a lower velocity because v=lambda*f hence giving a bigger n?
😕

the whole "bent" and "bending" has to do with comparing it to the original line the light would have followed had it not entered a different medium

when we say refract (in relation to the normal) blue light will have the smallest angle of refraction (in relation to the normal)

the index of refraction is affected by the frequency OR the wavelength...if we take frequency as an example we know that a highr frequency will interact w/ the medium more meaning it is more apt to slowing down where as a lower frequency will interact less and will be faster than light w/ a higher frequency.

hope that helps and i posted in my thread all the formulas that apply

it all has to do w/ snell's law and the fact that v= c/n

 

[pm1]

the whole "bent" and "bending" has to do with comparing it to the original line the light would have followed had it not entered a different medium

when we say refract (in relation to the normal) blue light will have the smallest angle of refraction (in relation to the normal)

the index of refraction is affected by the frequency OR the wavelength...if we take frequency as an example we know that a highr frequency will interact w/ the medium more meaning it is more apt to slowing down where as a lower frequency will interact less and will be faster than light w/ a higher frequency.

hope that helps and i posted in my thread all the formulas that apply

it all has to do w/ snell's law and the fact that v= c/n

thank you so much! I guess I was confusing with the "bending" and refracting terms!