In a single-slit diffraction experiment, the slit is illuminated by light of two wavelengths $$\lambda_1$$ and $$\lambda_2$$. It is observed that the $$2^{\text {nd }}$$ order diffraction minimum for $$\lambda_1$$ coincides with the $$3^{\text {rd }}$$ diffraction minimum for $$\lambda_2$$. Then

A ray of monochromatic light is incident on the plane surface of separation between two media $$\mathrm{X}$$ and $$\mathrm{Y}$$ with angle of incidence '$$\mathrm{i}$$' in medium $\mathrm{X}$ and angle of refraction 'r' in medium Y. The given graph shows the relation between $$\sin \mathrm{i}$$ and $$\sin \mathrm{r}$$. If $$\mathrm{V}_{X}$$ and $$\mathrm{V}_{Y}$$ are the velocities of the ray in media X and Y respectively, then which of the following is true?

X-rays of wavelength $$\lambda$$ gets reflected from parallel planes of atoms in a crystal with spacing d between two planes as shown in the figure. If the two reflected beams interfere constructively, then the condition for maxima will be, (n is the order of interference fringe)

An interference pattern is obtained with two coherent sources of intensity ratio n : 1. The ratio $$\mathrm{{{{I_{\max }} - {I_{\min }}} \over {{I_{\max }} + {I_{\min }}}}}$$ will be maximum if