Two slits are made one millimeter apart and the screen is placed one metre away. When blue-green light of wavelength 500 nm is used, the fringe separation is

Options

A. 0.1 nm
B. 0.125 nm
C. 0.5 mm
D. 0.1 mm

Answer

C

Explanation

Given, `D=1m, lambda=500 nm=5xx10^(-7)m`
` and d=1mm=1xx10^(-3)m`
Fringe separation, `beta=(Dlambda)/(d)`
`therefore beta=(1xx5xx10^(-7))/(1xx10^(-3))m=5xx10^(-4)m=0.5mm`