In Young's double slit experiment, the distance between two coherent sources is 1 mm and the distance between the slits and the screen is 1 m. If the 10th dark fringe is at a distance of 4.75 mm from the central bright fringe, calculate
the wavelength of light used and

Explanation

d=1 mm: D=1m, for `10^(th)` dark fringe n=10 ,
`x_n=4.75 mm`
For `5^(th)` bright fringe, n= 5
( For `n^(th)` dark fringe,
`x_n=((2n-1))/2betaimpliesx_n((2n-1))/2(lamdaD)/d`
`4.75 times10^-3=((2times10-1))/2 (lamdatimes1)/(1 times10^-3)`
`4.75times10^-3=(19lamda)/(2times10^-3)`
`lamda=9.5/19times10^-6=0.5 times10^-6=500mm`