question_answer

What change will occur in diffraction pattern if (i) light of smaller wavelength is used (ii) slit is made narrower, and (iii) another slit is placed near and parallel to the first slit?

Answer:

                Directions of various minima in a diffraction pattern are given by \[{{\theta }_{n}}=\frac{n\lambda }{d}\] (i) When light of smaller wavelength\[\lambda \] is used, the diffraction pattern becomes narrower. (ii) When d decreases, \[{{\theta }_{n}}\] increases and the diffraction pattern spreads out. (iii) Interference pattern replaces the diffraction pattern.