# Homework Help: How far is the ray displaced as a result of traveling through the gla

1. Feb 24, 2013

### lizaliiu

1. A ray of light passes from air through dense flint glass and then back into air. The angle of incidence on the first glass surface is 63.5°. The thickness of the glass is 4.26 mm; its front and back surfaces are parallel. How far is the ray displaced as a result of traveling through the glass?

this is what I tried...

1sin65.5=1.6sinA
sinA=0.5593
A=34.01°

x=4.26tan63.5°-4.26tan34.01°
= 5.671mm

I am no sure where i did wrong....

2. Feb 24, 2013

### SammyS

Staff Emeritus
Re: How far is the ray displaced as a result of traveling through the

You really need to provide a sketch of the situation for us to be of much help.

3. Feb 24, 2013

### haruspex

Re: How far is the ray displaced as a result of traveling through the

That's the distance between the point where the ray exited the glass and the point where it would have exited the glass had its index been 1. That is not the same as the distance between the two paths.