2014 AIPMT Wave OpticsSingle slit diffraction Easy Question 4 of 4 in Single slit diffraction

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:

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

The answer is D.

Solution

Width of central bright fringe $= \frac{2\lambda D}{a} = \frac{2\times600\times10^{-9}\times2}{1\times10^{-3}}$ m
$= 2.4\times10^{-3}$ m = 2.4 mm

Concept Width of central maximum

Single slit diffraction in past papers

4 questions from this chapter have appeared across 3 exam years.