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

_________________

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

__________________

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

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: TIR Question

**Physics Forums | Science Articles, Homework Help, Discussion**