I completed a question about TIR in a glass prism, and I was wondering if someone can tell me if I got it right. Thanks(adsbygoogle = window.adsbygoogle || []).push({});

"Less" and "more" refer to the less dense medium and more dense medium, and the red line is the normal.

http://img145.imageshack.us/img145/7061/tirquestion0mi.png [Broken]

Question: Determine all the necessary angles and then calculate at which angle the ray exits the prism. n= 1.44

Calculations:

n= sin less/sin more

1.44= sin 62/sin more

sin 62/1.44= sin more

angle more= 38

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n= sin less/sin more

1.44= sin less/ sin 60

angle less= N/A

therefore, sin C= 1/n

sin C= 1/1.44

= 0.6944

Critical angle= 44

angle more is greater than critical angle, therefore TIR occurs

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n= sin less/sin more

1.44= sin less/ sin 20

angle less= 30

The ray exits the prism at 30 degrees.

EDIT: I put the 62 in the wrong place, I meant it to be in between the normal and ray

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# TIR Question

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