How Do You Calculate Angle Θ and Deflection Φ in Refraction Problems?

[tstu12]

Homework Statement

here is a picture of what is given: http://img838.imageshack.us/i/physicsproblem.png/

I am supposed to find the measure of angle Θ and by what amount Φ is the ray deflected from its original path.

from what is given i know that the angle of incidence is 35 degrees correct? and the angle of refraction using snell's law (n1sinΘ1=n2sinΘ2) is then 22.5 degrees? where do i go from here to find the answer of the 2 questions above?


(The n outside of the triangle is 1.0 and the n inside the triangle is 1.5)

I'm not looking for someone to give the solution I'm looking for someone to point me in the right direction to the solution, I've been trying this problem a couple different ways and can't seem to figure it out. thanks!

The Attempt: This is what i have found, i don't know where to go from here or if what i have found is correct: http://img153.imageshack.us/img153/41/physicsproblemattempt.png

 

[rl.bhat]

Simple geometry shows that A = r1 + r2.
In the problem, A is given. You have found out r1. Find r2.
n = sin(θi2)/sin(r2)
Deviation δ1 in the first face is θi1 - r1 and in the second surface is δ2 = θi2 - r2.
Total deviation d = δ1 + δ2.

 

[rl.bhat]

Simple geometry shows that A = r1 + r2.
In the problem, A is given. You have found out r1. Find r2.
n = sin(θi2)/sin(r2)
Deviation δ1 in the first face is θi1 - r1 and in the second surface is δ2 = θi2 - r2.
Total deviation d = δ1 + δ2.

 

[tstu12]

this is what i did: http://img193.imageshack.us/i/physicsproblemattempt.png/

Is that correct?

 

[rl.bhat]

Your answer is correct.