A fringe width of 6 mm was produced for two slits separated by 1 mm apart. The screen is placed 10 m away. The wavelength of light used is 'x' nm. The value of 'x' to the nearest integer is _ _ _ _ .
Solution
Fringe width = 6mm=λDd=λ×101×10−3
⇒λ=6×10−3×10−310=6×10−7=600nm
∴x=600