Solving for Total Internal Reflection: Find Another Way!

AI Thread Summary
The discussion focuses on finding the conditions for total internal reflection using the equation n1sin(θ1) = n2sin(θ2). The user is trying to determine the refractive index n2, given n1 = 1, θ1 = 44 degrees, and θ2 = 48 degrees. There is confusion regarding the interpretation of the angles and the sine function, with clarifications requested about the angles involved. The user describes an experiment involving a semi-circular slab to observe total internal reflection but is unsure how to calculate the necessary values. The conversation emphasizes the need for clarity in the equations and the correct application of the principles of optics.
Awsom Guy
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Homework Statement


To find the total internal reflection.
This equation should give me 1.48 as the answer but it doesn't. Can you please give me other ways to figure this out. I really need this.

Homework Equations


n1sin1Ө=n2sin2Ө
n1 = 1
n2 =?
sin1Ө = 44 degrees
sin2Ө = 48 degrees


The Attempt at a Solution

 
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Show us your work so far. Also the sine of an angle can't be equal to some degrees. Do you mean that \theta_1=44^\circ , \theta_2=48^\circ?
 
What precisely do you want to find, n2?

What do you mean by "sin1Ө" and "sin2Ө"? Are they the sines of Ө and two times Ө, or the sines of two different angles (Ө1 and Ө2)? Also, the sine of an angle is not measured in degrees, so what are the last two lines? Did you mean that Ө is 44 and/or 48 degrees?
 
Cyosis said:
Show us your work so far. Also the sine of an angle can't be equal to some degrees. Do you mean that \theta_1=44^\circ , \theta_2=48^\circ?

yes i do mean that.
 
CompuChip said:
What precisely do you want to find, n2?

What do you mean by "sin1Ө" and "sin2Ө"? Are they the sines of Ө and two times Ө, or the sines of two different angles (Ө1 and Ө2)? Also, the sine of an angle is not measured in degrees, so what are the last two lines? Did you mean that Ө is 44 and/or 48 degrees?

Yes that is exactly it.
 
We arranged the semi circular slab so that a single light ray strikes the curved side and passes through to the other side. We then turned the semi circular slab and turned until there was no refraction. That is when we found out when total internal reflection happened.
Now I don't know how to get the results for this. That is my problem. The above eqaution was meant to be used, but it might not be the answer.
 
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