Question

In an interference experiment two parallel vertical slits $S_1$ and $S_2$ are used. A thin glass plate is introduced in the path of light from $S_1$. Then

• A. fringe pattern remains unaltered
• B. fringe pattern as a whole is laterally shifted towards $S_1$
• C. fringe pattern as a whole is laterally shifted towards $S_2$
• D. fringe width decreases

Answer 1

Answer: (B)

fringe pattern as a whole is laterally shifted towards $S_1$

Answer 2

As a thin glass plate is introduced in the path of light from $S_1$ in Young's double slit experiment arrangement, so fringe pattern as a whole is laterally shifted towards $S_1$.