Thank you for reporting, we will resolve it shortly
Q.
In Young's double-slit experiment, $d=0.1mm$ , $D=20cm$ , and $\lambda =5460 \, Å$ , the angular position of first dark fringe will be
NTA AbhyasNTA Abhyas 2022
Solution:
Position of dark fringe $y=\left(2 n - 1\right)\frac{\lambda }{2}\times \frac{D}{d}=\frac{\lambda }{2}\times \frac{D}{d}$
$\therefore $ Also $\theta =\frac{y}{D}$
$=\frac{\lambda }{2 d}=2730\times 10^{- 6}\times \frac{180}{\pi }=0.16^{o}$