Question

In Young's double slit experiment, the fringe width is $\beta$. If the entire arrangement is placed in a liquid of refractive index n, the fringe width becomes

• A. $n\beta$
• B. $\frac{\beta }{n+1}$
• C. $\frac{\beta }{n-1}$
• D. $\frac{\beta }{n}$

Answer 1

The correct option is D $\frac{\beta }{n}$

The fringe width decreases when the arrangement is placed in a liquid of refractive index n, so the final fringe width becomes $\frac{B}{n}$.