Reflection/Refraction homework help

[3gowns]

Homework Statement

A light ray is incident on a glass prism with n=1.65. (A) If the prism is immersed in air, where does the light ray emerge into the air? At what angle? (B) If the prism is immersed in water, where does the light emerge into the water? At what angle?

_____ A_____C
_____ |90 45/
_____ |____/
----->|___/
_____ |n /
_____ B /

Homework Equations

n_a sin(theta_a) = n_b sin(theta_b)
sin(theta)critical= n_b/n_a

The Attempt at a Solution

PART A:

AB)
1.0 sin(0)= 1.65 sin(theta)'
(theta)'= 0 (no bending)

BC) (crtitical angle 41.1 in air?)
1.65 sin 45 = 1.52 sin (theta)'
(theta)'= 50.14 <- final answer

PART B:
just change the n's?

Any good?

 

[mgb_phys]

B, yes n for water is around 1.3