Question

In the YDSE shown below, two slits are covered with thin sheets having thickness $t$ and $2t$ and refractive indices $2\,\mu $ and $\mu $ respectively. The position of central maxima is shifted by a distance of $N$ (in cm) from central position of screen. Find the value of $N$ .
$\left[d = 1 \,mm , D = 1 \,m , t = 2 \times 10^{- 2} mm , \mu = \frac{3}{2}\right]$

Answer 1

Hint : $d \sin \theta=2 \mu t+t-2 \mu t$
Solution : $d \sin \theta=2 \mu t+t-2 \mu t$
$\Rightarrow d \frac{y}{D}=t \Rightarrow y=\frac{D t}{d} $
$\Rightarrow y=\frac{1 \times 2 \times 10^{-5}}{1 \times 10^{-3}}=2 \times 10^{-2} m$