Answer:
Width of central bright fringe will be 0.00228 m
Explanation:
We have given wavelength of light [tex]\lambda =632.8nm=632.8\times 10^{-9}m[/tex]
Distance between the slits [tex]d=0.5mm=0.5\times 10^{-3}m[/tex]
Distance between slit and screen D = 1.8 m
We have to find the width
We know that width is given by
[tex]width=\frac{\lambda D}{d}=\frac{632.8\times 10^{-9}\times 1.8}{0.5\times 10^{-3}}=0.00228m[/tex]
So width of central bright fringe will be 0.00228 m