Optics Question 1090
Question: If yellow light in the Young’s double slit experiment is replaced by red light, the fringe width will
[MP PMT 1996]
Options:
A) Decrease
B) Remain unaffected
C) Increase
D) First increase and then decrease
Show Answer
Answer:
Correct Answer: C
Solution:
Fringe width $ (\beta )=\frac{D\lambda }{d}\Rightarrow \beta \propto \lambda $ As $ {\lambda _{red}}>{\lambda _{yellow}}, $ hence fringe width will increase.