$A$ slit of size $0.15 \ cm$ is placed at $2.1 \ m$ from a screen. On illuminating it by a light of wavelength $5 \times 10^{-5} \ cm$,the width of the central maxima will be:

Maximum diffraction takes place in a given slit for

Assertion: The clouds in the sky generally appear to be whitish.
Reason: Diffraction due to clouds is efficient in equal measure at all wavelengths.

$A$ beam of light having wavelength $5400 \text{ Å}$ from a distant source falls on a single slit $0.96 \text{ mm}$ wide and the resultant diffraction pattern is observed on a screen $2 \text{ m}$ away. What is the distance between the first dark fringe on either side of the central bright fringe (in $\text{mm}$)?

$A$ narrow slit of width $2 \, mm$ is illuminated by monochromatic light of wavelength $500 \, nm$. The distance between the first minima on either side on a screen at a distance of $1 \, m$ is ........ $mm$.

Monochromatic light of wavelength $580 \,nm$ is incident on a slit of width $0.30 \,mm$. The screen is $2 \,m$ from the slit. The width of the central maximum is ........... $\times 10^{-3} \,m$.