A) \[500\text{ }nm\]
B) \[600\text{ }nm\]
C) \[400\text{ }nm\]
D) \[300\text{ }nm\]
Correct Answer: C
Solution :
Fringe width \[W=\frac{D\lambda }{d}\] Given. \[d=0.4\,mm=0.04\,cm,\,D=200\,\,cm\] \[W=2mm=0.2\,cm\] \[\therefore \] \[0.2=\frac{200\times \lambda }{0.04}\] \[\Rightarrow \]\[\lambda =400nm\]You need to login to perform this action.
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