Optics Question 192
Question: In Young’s double slit experiment intensity at a point is (1/4) of the maximum intensity. Angular position of this point is
[IIT-JEE (Screening) 2005]
Options:
A) sin-1(l/d)
B) sin-1(l/2d)
C) sin-1(l/3d)
D) sin-1(l/4d)
Show Answer
Answer:
Correct Answer: C
Solution:
$ I=4I _{0} $ cos2(f/2)
Therefore f = 2p/3
Therefore Dx x (2p/l) = 2p/3= l/3 sin q = Dx/d
Therefore sin q = l/3d