Snell's Law x2: Double-checking trig?

AI Thread Summary
The discussion revolves around applying Snell's Law to determine the angles of light as it transitions between glass and carbon disulfide. The user calculates the angle of refraction within the glass as 47° and subsequently finds the angle as light exits back into carbon disulfide to be approximately 39.5°. The calculations utilize the indices of refraction for both materials and confirm the angles using trigonometric principles. Participants in the thread affirm the correctness of the user's approach and results. Overall, the method and final angles are validated as accurate.
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Homework Statement



In this drawing:

http://img245.imageshack.us/img245/6559/physgv8.png

Index of refraction for glass: 1.52
Index of refraction for surrounding carbon disulfide: 1.63
Incident angle at point A: 43.0°
At what angle does the ray leave the glass at point B?

Homework Equations



n_{1}sin\theta_{1} = n_{2}sin\theta_{2} (twice)

The Attempt at a Solution



Please double-check my conceptual understanding of this.

Part 1, as light travels through the carbon disulfide into the glass:

1.63sin43 = 1.52sin\theta_{2}

\theta_{2} = sin^{-1}\frac{1.63sin43}{1.52}

So Θ within the glass is 47°.

Drawn out and making a triangle with the upper left hand corner of the glass, a triangle forms with point B as one of its own points, meaning that the angle with a normal line at that point would be 180 - (90 + 47) = 43°.

Part 2, as light travels through the glass back into the carbon disulfide:

1.52sin43 = 1.63sin\theta_{2}

\theta_{2} = sin^{-1}\frac{1.52sin43}{1.63}

Which yields 39.4923°.

Am I going about this correctly?
 
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Looks OK to me.
 
hage567 said:
Looks OK to me.

Thanks for taking a peek - turned out to be correct.
 
Looks correct to me too.
 
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