Optics Question 155
Question: In Young’s double slit experiment how many maxima’s can be obtained on a screen (including the central maximum) on both sides of the central fringe if $ \lambda =2000{AA} $ and $ d=7000{AA} $
Options:
A) 12
B) 7
C) 18
D) 4
Show Answer
Answer:
Correct Answer: B
Solution:
For maximum intensity on the screen $ d\sin \theta =n\lambda \Rightarrow \sin \theta =\frac{n\lambda }{d}=\frac{n(2000)}{7000}=\frac{n}{3.5} $
Since maximum value of $ \sin \theta $ is 1 So $ n=0,1,2,3, $ only.
Thus only seven maximas can be obtained on both sides of the screen.