What is the index of refraction of this unknown material?

[cjhockey35]

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$\theta$2 / sin$\theta$1 = 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

 

[abaden]

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

 

[ap123]

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?

 

[Basic_Physics]

Your calculator was set for radians, not degrees.

 

[Nickie]

I would first check my calculations to ensure they are accurate. It looks like you have correctly applied the equation for Snell's law, but the value of n2 that you have calculated (.504) is not one of the given options. This could mean that there is an error in your calculations or that the options are incorrect. I would recommend double-checking your work and also considering if there are any other equations or information that could help you determine the index of refraction more accurately. Additionally, it is always helpful to provide units for your answer, as the index of refraction is a dimensionless quantity.