Light of wavelength $\lambda$ is incident on a single slit of width $a$ and the distance between the slit and the screen is $D$. In the diffraction pattern, if the slit width is equal to the width of the central maximum, then $D$ is equal to:

In an experiment,electrons are made to pass through a narrow slit of width $'d'$ comparable to their de-Broglie wavelength. They are detected on a screen at a distance $'D'$ from the slit (see figure). Which of the following graphs can be expected to represent the number of electrons $'N'$ detected as a function of the detector position $'y'$ ($y = 0$ corresponds to the middle of the slit)?

$A$ diffraction pattern is obtained using a beam of red light. If red light is replaced by blue light,then:

The diffraction fringes obtained from a single slit are.....

Write the condition of $n^{th}$ order maximum in diffraction.

$A$ plane wavefront of monochromatic light is incident normally on a narrow slit. $A$ diffraction pattern is formed on a screen. What is the phase difference between the waves originating from the top and bottom edges of the slit at the position of the first minimum?