Q. Two parallel slits $0.6\ mm$ apart are illuminated by light source of wavelength $6000\ \mathring{\mathrm{A}}$. The distance between two consecutive dark fringes on a screen $1\ m$ away from the slits is
A) $1\ mm$
B) $0.01\ mm$
C) $0.1\ m$
D) $10\ m$
Explanation
(a) Distance between two consecutive
Dark fringes $= \frac{\lambda D}{d} = \frac{6000 \times 10^{- 10} \times 1}{0.6 \times 10^{- 3}}$
$= 1 \times 10^{- 3}m = 1mm$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.