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Incidences of refraction

  • #1

Homework Statement


I am preparing for a test. I really need help with this is problem. I uploaded a picture for the figure.
The figure below shows the path of a beam of light through several layers (n1 = 1.58, n2 = 1.39, n3 = 1.21 and n4 = 1.00) of different indices of refraction.

PART1 ASKS:
If
mimetex.gif
= 29.1o, what is the angle,
mimetex.gif
, of the emerging beam?

PART 2:
What must the incident angle,
mimetex.gif
, be in order to have total internal reflection at the surface between the n3 = 1.21 medium and the n4 = 1.00 medium?


Homework Equations



We have to use Snell's Law: which is n1sin=n2sin

The Attempt at a Solution



FOR PART 1: This is what I did:
I know N for 1 and 2. The angle is 29.1 as given. So....
[/B]
mimetex.gif
sin^-1=(n1/n2*sin) sin^-1=(1.58/1.39*sin29.1). I get .662 which is off.

For Part 2: I am clueless.

Please guide me.
 

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Answers and Replies

  • #2
rude man
Homework Helper
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mimetex.gif
sin^-1=(n1/n2*sin) sin^-1=(1.58/1.39*sin29.1). I get .662 which is off.
Your equation makes no sense to me. Try again? Start with Snell's law again, carefully.
 

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