Arun
Last Activity: 4 Years ago
If the screen distance id D, distance between the slits is d and the wave length is λ
then the fringe width is given by
b = λD/d
When the arrangement is immerse in a liquid of refractive index u then the new wavelength is 1/u times the original wavelength
If the new wavelength is λ' then
λ' = λ/n
Therefore, the new fringe width will be
b' = λ'D/d
or, b' = b/u
Therefore the fringe width will decrease by a factor of u.