Q.
Diffraction pattern from a single slit of width 0.25mm is observed with light of wavelength 5890A˚. Angular separation between first order minimum and third order maximum, falling on the same side, is
In single slit diffraction pattern, positions of secondary maxima and minima are given by, θmax=±(2n+1)2dλ and θmin=±ndλ, respectively. ∴θ1min=dλ and θ3max=2d7λ
Angular separation =θ3max−θ1min=2d7λ−dλ =2d5λ=25×0.25×10−35890×10−10=5.89×10−3 rad.