Q. In Young’s double slit experiment, phase difference between light waves reaching 3$^{rd}$ bright fringe from the central fringe when $\lambda = 5000\ \mathring{\mathrm{A}}$is
A) $6\ \pi$
B) $2\ \pi$
C) $4\ \pi$
D) $zero$
Explanation
(a) Path difference of 3$^{rd}$ bright fringe from central fringe=$3\lambda$, so that the phase difference=$3(2\pi) = 6\pi\ rad$.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.