Finding index of refraction using total internal reflection

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Cocoleia
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Homework Statement


I need to describe an experiment in which I would use internal reflection to determine the index of refraction of material

Homework Equations



Snell's law

The Attempt at a Solution


I understand the concept of internal reflection, such as the critical angle etc. I am just unsure of what kind of experiment could let me determine the index of refraction
 
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Cocoleia said:

Homework Statement


I need to describe an experiment in which I would use internal reflection to determine the index of refraction of material

Homework Equations



Snell's law

The Attempt at a Solution


I understand the concept of internal reflection, such as the critical angle etc. I am just unsure of what kind of experiment could let me determine the index of refraction
Can you show us a diagram of the critical angle, and show us the equation you would use to calculate the angle for TIR?
 
And how is that angle dependent on the two indices of refraction of the two materials at the boundary?
 
berkeman said:
And how is that angle dependent on the two indices of refraction of the two materials at the boundary?
Critical angle = inverse sin(nr/ni
Once we reach the critical angle we will have total internal reflection.
 
Cocoleia said:
Critical angle = inverse sin(nr/ni
Once we reach the critical angle we will have total internal reflection.
So if you know the index for the lower index material, and can control the angle of incidence into the boundary, you should be able to determine the unknown index experimentally, right? :smile: