Answer:
214.3 x 10⁻⁹ m or 214.3 nm
Step-by-step explanation:
= slit separation in the experiment = 3.00 x 10⁻⁵ m
= screen distance from the slits = 2.00 m
= Order of the bright fringe = 7
λ = Wavelength of the light
= distance of the bright fringe from the central bright fringe = 10 cm = 0.10 m
Position of the bright fringe is given as


λ = 214.3 x 10⁻⁹ m
λ = 214.3 nm