Question

In Young's double slit experiment, intensity at a bright fringe is $I_0$. One of the slits is closed. Intensity at the same position is

• A. $\frac{I_0}{2}$
• B. $I_0$
• C. $\frac{I_0}{4}$
• D. zero

Answer 1

Answer: (C)

$\frac{I_0}{4}$

Answer 2

Intensity of the bright fringe = $I_0$
We know, maximum intensity of a bright fringe
$I_0 = 4 \times$ Intensity of ligh,t through one slit
$\therefore$ Intensity of light through one slit = $\frac{I_0}{4}$
Intensity at the point of bright fringe.