Q.

Two wavelengths λ1 and λ2 are used in Young's double slit experiment. λ1 = 450 nm and λ2 = 650 nm. The minimum order of fringe produced by λ2 which overlaps with the fringe produced by λ1 is n. The value of n is ____.                   [2024]


Ans.

(9)          m2λ2=m1λ1

              m2m1=λ1λ2=450650=913

             i.e. 9th maxima of λ2 overlaps with 13th maxima of λ1.

            n=9