# Rainbow blob

1. Jun 21, 2011

### Lindsayyyy

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 $$n_{1}=1.46$$and $$n_{2}1.47$$ Now I want to calculate the angle $$\delta$$

2. Relevant equations

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

$$360°= \delta+\alpha+\alpha+(360°-4\beta)$$

and

$$\delta= 4\beta-2\alpha=4arcsin(\frac {1} {n} sin\alpha)-2\alpha$$

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?

2. Jun 21, 2011

### Clever-Name

What angle are you trying to calculate? Maybe it's just me but it isn't clear to me what angle is in question.

3. Jun 21, 2011

### Lindsayyyy

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.

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