Question

At the first minima, adjacent to the central maxima of a single - slit diffraction pattern, the phase difference between the Huygen's wavelet from the edge of the slit and the wavelet from the midpoint of the slit is

• A. $\frac{\pi }{8}$ radian
• B. $\frac{\pi }{4}$ radian
• C. $\frac{\pi }{2}$ radian
• D. $\pi$ radian

Answer 1

The correct option is D $\pi$ radian


$ForfirstminimaatP,a\sin \theta =\lambda So,phasedifference\Delta {\varphi }_1=\frac{\Delta x_1}{\lambda }\times 2\pi =\frac{\left(a/2\right)\sin \theta }{\lambda }\times 2\pi \Delta {\varphi }_1=\frac{\lambda }{2\lambda }\times 2\pi =\pi radian$