$A$ light ray of wavelength $\lambda$ is passing through a pinhole of diameter $D$ and the effect is observed on a screen placed at a distance $L$ from the pinhole. The approximations of geometrical optics are applicable, if

In a single slit diffraction pattern, the distance between the plane of the slit and the screen is $1.4 \text{ m}$. The width of the slit is $0.66 \text{ mm}$. The second maximum is formed at the distance of $2.8 \text{ mm}$ from the center of the screen. The wavelength of light used is (in $\text{ Å}$)

In a single-slit diffraction experiment,what is the width of the slit $(b)$ such that $20$ maxima of a double-slit interference pattern are obtained within the central maximum of the diffraction pattern? (Given: Slit separation for the double-slit arrangement $d = 2 \, mm$)

In a laboratory,diffraction due to a single slit is observed. If the slit is made slightly narrower,then the diffraction pattern will:

$A$ single slit of width $b$ is illuminated by a coherent monochromatic light of wavelength $\lambda$. If the second and fourth minima in the diffraction pattern at a distance $1\,m$ from the slit are at $3\,cm$ and $6\,cm$ respectively from the central maximum,what is the width of the central maximum in $cm$ (i.e.,distance between the first minimum on either side of the central maximum)?

The ratio of intensities of consecutive maxima in the diffraction pattern due to a single slit is