In a Young's experiment, the distance between two slits is 0.2 mm. If the wavelength of light used in this experiment is 5000 Å, then the distance of 3rd bright fringes from central maxima will be ......

Options

A. `0.75`
B. `0.075`
C. `0.0075`
D. `0.057`

Answer

C

Explanation

For `n^(th)` bright, fringe,
In `d sin theta= n lambda`
`n=3, d=0.2 cm lambda=5xx10^(-5) cm`
`:. sin theta=(n lambda)/(d)=(3xx5xx10^(-5))/(0.02)`
`sin theta=(0.015)/(2)=0.0075`
`:. sin theta =0.0075` rad