Question

In Youngs double slit experiment with sodium vapour lamp of wavelength 589 nm and the slits 0.589 mm apart, the half angular width of the central maximum is

• A. $ {{\sin }^{-1}}(0.01) $
• B. $ {{\sin }^{-1}}(0.0001) $
• C. $ {{\sin }^{-1}}(0.001) $
• D. $ {{\sin }^{-1}}(0.1) $

Answer 1

Answer: (C)

In Youngs double slit experiment half angular width is given by
$ \sin \theta =\frac{\lambda }{d} $
$ \sin \theta =\frac{589\times {{10}^{-9}}}{0.589\times {{10}^{-3}}}={{10}^{-3}} $
$ \theta ={{\sin }^{-1}}(0.001) $