In Young's doulbe-slit experiment the separation between two coherent sources `S_(1)` and `S_(2)` is d and the distance between the source and screen is D. In the interference pattern, it is found that exactly in front of one slit, there occurs a minimum. Then the possible wavelengths used in the experiment are

Options

A. (a) `lambda=d^2/D, (d^2)/(3D), (d^2)/(5D)`
B. (b) `lambda=(d^2)/(D), (d^2)/(5D), (d^2)/(9D)`
C. (c) `lambda=(d^2)/(D), (d^2)/(2D), (d^2)/(3D)`
D. (d) `lambda=(d^2)/(3D), (d^2)/(7D), (d^2)/(11D)`

Answer

A

Explanation

`y=d/2=(2(n-1)Dlambda)/(2d)`
`implieslambda=(d^2)/(D(2n-1)), n=1,2,3`