$A$ diffraction pattern is obtained by using a beam of red light. What will happen if the red light is replaced by blue light?

Light of wavelength $589.3 \, nm$ is incident normally on a slit of width $0.1 \, mm$. What will be the angular width of the central diffraction maximum in degrees?

The light of wavelength $6328 \ \mathring{A}$ is incident on a slit of width $0.2 \ mm$ perpendicularly. The angular width of the central maxima will be.....$^o$

Which of the following statements are correct with reference to single slit diffraction pattern?
$(I)$ The central maxima is twice as wide as the secondary maxima.
$(II)$ The intensity of secondary maxima decreases as we move away from the central maxima.
$(III)$ The width of the central maxima is independent of the slit width.
$(IV)$ The intensity of the central maxima is the same as that of the secondary maxima.

To observe diffraction,the size of an obstacle:

The first diffraction minima due to a single slit diffraction is at $\theta = 30^o$ for a light of wavelength $5000 \,\mathring{A}$. The width of the slit is