Adouble-slit arrangement produces interference fringes for sodium light (λ = 589 nm) that are 0.48° apart. what is the angular fringe separation if the entire arrangement is immersed in a liquid that has index of refraction n = 1.25?

0.38°

Explanation:

= Angle

m = Number

d = Distance

n = Refractive index of liquid = 1.25

a denotes air

l denotes liquid

In the case of double split interferance we have the relation

For air

For liquid

Dividing the two equations

Wavelength ratio =

The angular separation is 0.38°

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