Two coherent light sources `S_1` and `S_2 (lambda=6000Å)` are `1mm` apart from each other. The screen is placed at a distance of `25cm` from the sources. The width of the fringes on the screen should be

Options

A. (a) `0.015cm`
B. (b) `0.025cm`
C. (c) `0.010cm`
D. (d) `0.030cm`

Answer

A

Explanation

`beta=(6000xx10^(-10)xx25xx10^-2)/(10^-3)`
`=150000xx10^-9=0.15xx10^-9`
`=0.15xx10^-3m=0.015cm`.