Which one of the following expressions gives the fringe width in a Young’s…

PHYSICS · Single correct · A Level · Physics · Waves · Waves

Problem

Which one of the following expressions gives the fringe width

\beta

in a Young’s double-slit experiment in terms of slit separation

d

, distance to the screen

D

, and wavelength

\lambda

? (a)

\displaystyle \beta = \dfrac{d\lambda}{D}

(b)

\displaystyle \beta = \dfrac{\lambda D}{2d}

(c)

\displaystyle \beta = \dfrac{\lambda D}{d}

(d)

\displaystyle \beta = \lambda\sqrt{\dfrac{D}{d}}