In a diffraction pattern due to a single slit of width \['a',\] the first minimum is observed at an angle \[{{30}^{o}}\] when light of wavelength \[5000\text{ }\overset{o}{\mathop{A}}\,\] is incident on the slit. The first secondary maximum is observed at an angle of : [NEET - 2016]
A) \[{{\sin }^{-1}}\left( \frac{1}{4} \right)\]
B) \[{{\sin }^{-1}}\left( \frac{2}{3} \right)\]
C) \[{{\sin }^{-1}}\left( \frac{1}{2} \right)\]
D) \[{{\sin }^{-1}}\left( \frac{3}{4} \right)\]
Correct Answer:
D
Solution :
[d] For first minima, \[\sin {{30}^{o}}=\frac{\lambda }{a}=\frac{1}{2}\]