Finding the deviation angle δ for red and violet light in rainbows

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Lindsayyyy
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Hi everyone

Homework Statement



Let's say we observe a rainbow. We know the refraction index of the red and violet light, let's call them [tex]n_{1}=1.46[/tex]and [tex]n_{2}1.47[/tex] Now I want to calculate the angle [tex]\delta[/tex]




Homework Equations



In a square the total angle is 360°, so we have:

[tex]360°= \delta+\alpha+\alpha+(360°-4\beta)[/tex]

and

[tex]\delta= 4\beta-2\alpha=4arcsin(\frac {1} {n} sin\alpha)-2\alpha[/tex]




The Attempt at a Solution



Thats my attempt thus far, which I wrote down in the relevant equations. I have two unkown variables, alpha and delta and I want to calculate alpha. Is there a way to calculate alpha in order to get delta?

Thanks for your help
 
What angle are you trying to calculate? Maybe it's just me but it isn't clear to me what angle is in question.
 
Wow, I failed, I wanted to attach a file, sorry for that. I want to calculate delta, but I need to find alpha first and I don't know how.
 
Attachments
  • Hand-drawn ray diagram of a raindrop on grid paper: an incoming ray hits the circle at the top, refracts inside with angles labelled alpha, beta and gamma, reflects off the far side and exits at the bottom, with the total deviation angle labelled delta.
    Unbenannt.JPG
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