In Young's double slit experiment, the distance between two sources is `0.1mm`. The distance of screen from the sources is `20cm`. Wavelength of light used is `5460Å`. Then angular position of the first dark fringe is

Options

A. `0.08^(@)`
B. `0.16^(@)`
C. `0.20^(@)`
D. `0.31^(@)`

Answer

B

Explanation

Angular position of first dark fringe
` theta_(1)=(2xx1-1)(lambda)/(2d)=(lambda)/(2d)=(5460xx10^(-10))/(2xx0.1xx10^(-3))=2730xx10^(-6)`rad
` " " =2730xx10^(-6)xx (180)/(pi)=0.16^(@)`.