A beam of light of wavelength `600nm` from a distant source falls on a single slit `1mm` wide and the resulting diffraction pattern is observed on a screen `2m` away. The distance between the first dark fringes on either side of the central bright fringe is
A. (a) `1.2mm`
B. (b) `1.2cm`
C. (c) `2.4cm`
D. (d) `2.4mm`
A. (a) `1.2mm`
B. (b) `1.2cm`
C. (c) `2.4cm`
D. (d) `2.4mm`
Correct Answer – D
Distance between the first dark fringes on either side of central maxima=width of central maxima
`=(2lambdaD)/(d)=(2xx600xx10^-9xx2)/(1xx10^-3)=2.4mm.`