Interference fringes were produced in young's double  slit experiment using light of wave
Channel: Doubtnut
Date: 2020-08-16

Interference fringes were produced in young's double  slit experiment using light of wave length `5000Å`,When a film of material `2.5xx10^(-3)`cm thick was placed over over of the slits,the fringe pattern shifted by adistance equal to `20`fringe width.The refractive index of the material of the film is-