What is the index of refraction of this unknown material?

AI Thread Summary
The discussion revolves around calculating the index of refraction for an unknown material when light passes from air into it at specific angles. The correct formula to use is sin(θ2) / sin(θ1) = n1 / n2, where n1 is the index of refraction of air. The initial calculation yielded an incorrect value due to using radians instead of degrees, leading to confusion with the multiple-choice answers provided. Participants emphasized the importance of ensuring the calculator is set to degrees and noted that the refracted angle being less than the incident angle indicates that the unknown material has a higher index of refraction than air. Accurate calculations are crucial for arriving at the correct answer.
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Homework Statement



A beam of light travels through air (n= 1.0003) and strikes an unknown material at an angle of 50.0 degrees. The new angle of refraction is 25.0 degrees. What is the index of refraction of this material?

Homework Equations



sin\theta2 / sin\theta1 = n1/n2


The Attempt at a Solution



sin(25)/sin(50) = 1.0003/n2

.504 = 1.0003/n2

.504= n2


---It is multiple choice test and my answer isn't any of the options. The options are

A) .709
B) .643
C) 1.20
D) 1.81
 
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Try writing sin(θ1)/sin(θ2) = n1/n2 as an equation where n2 = n1 / ... . Then plug in your variables all at once and compute (you may be loosing accuracy by not capturing enough digits).

Edit: Also, remember radians = degrees * 180 / \pi.


Alex
 


The equation you're using is the correct one.

Your value for sin(25)/sin(50) is not correct, ( you're using radians instead of degrees )
Also, going from the 2nd to the 3rd line of your solution is wrong.

Note that the refracted angle is less than the incident angle - what does that tell you about n2?
 
Your calculator was set for radians, not degrees.
 
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