A beam of light of `lambda` = 600 nm from a distant source falls on a single slit 1 mm wide and the resulting diffraction pattern is observed on a screen 2 m away. The distance between first dark fringes on either side of the central bright fringe is

Options

A. 1.2 cm
B. 1.2 mm
C. 2.4 cm
D. 2.4 mm

Answer

D

Explanation

Given: `D=2m,d=1mm=1xx10^(-3)m`
`lamda=600nm=600xx10^(-6)m`
Width of central bright fringe `(=2beta)`
`=(2lamdaD)/d=(2xx600xx10^(-6)xx2)/(1xx10^(-3))m=2.4mm`