Question

What is the fringe width \(\beta\) in Young's double-slit experiment?

Options

• \[\beta=\frac{\lambda d}{D}\]

• \[\beta=\frac{\lambda D}{d}\]

• \[\beta=\frac{dD}{\lambda}\]

• \[\beta=\frac{D}{\lambda d}\]

Answer 1

Fringe width is the distance between successive bright fringes or successive dark fringes. That spacing is \[\beta=\frac{\lambda D}{d}\].