Optical path difference caused by double slit

[desmond iking]

Homework Statement

In this question, when S2 is covered with a very thin glass, the fringe move toward Y . why is it so?

Homework Equations

The Attempt at a Solution

 

[NascentOxygen]

What do you think might be going on here?

 

[desmond iking]

Only The light originate from s2 will pass thru the thin glass.

 

[NascentOxygen]

Only The light originate from s2 will pass thru the thin glass.

List the things you know happen when light passes from one medium through another.

 

[desmond iking]

Refraction happen

 

[NascentOxygen]

Refraction happen

And others?

http://imageshack.com/a/img811/5412/thgooglefriend1.gif

 

[desmond iking]

And others?

http://imageshack.com/a/img811/5412/thgooglefriend1.gif

as i know , only refraction happen. after googling, i also get refraction happen.