Question

The path difference between two monochromatic waves meeting at a point is 85.5lambda . If the path difference is 42.75 micrometer discuss whether the point is bright or dark also find wavelength is light

Answer 1

Answer:point is dark and λ=0.5μm

Explanation:

Given path difference is 85.5λ which can be written as (86-1/2)λ which is of the form (n-1/2)λ hence destructive interference will take place and ddark fringe will be form.

path difference=(n-1/2)λ

λ=$\frac{path difference}{(n-1/2)}$

put values in above equation you will get  λ=0.5μm

hope it helps.