NEET-XII-Physics
qstns with ansrs year:2022
- #31In a Young's double slit experiment, a student observes `` 8 `` fringes in a certain segment of screen when a monochromatic light of `` 600 \,nm `` wavelength is used. If the wavelength of light is changed to `` 400\, nm `` , then the number of fringes he would observe in the same region of the screen is :
(A)12
(B)6
(C)8
(D)9digAnsr: AAns : `` y=(n \lambda)\left(\frac{D}{d}\right) ``
`` n _{1} \lambda_{1}= n _{2} \lambda_{2} ``
`` (8) (600 \,nm )= n _{2}(400) ``
`` n _{2}=12 ``