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Homework Help: Rainbow blob

  1. Jun 21, 2011 #1
    Hi everyone

    1. The problem statement, all variables and given/known data

    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]

    2. Relevant equations

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

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


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

    3. 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
  2. jcsd
  3. Jun 21, 2011 #2
    What angle are you trying to calculate? Maybe it's just me but it isn't clear to me what angle is in question.
  4. Jun 21, 2011 #3
    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.

    Attached Files:

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