The phenomenon of diffraction occurs in .......

In a Fraunhofer's diffraction obtained by a single slit aperture,the value of path difference for $n^{th}$ order of minima is

$A$ wavefront presents one,two and three $HPZ$ at points $A, B$ and $C$ respectively. If the ratio of consecutive amplitudes of $HPZ$ is $4 : 3$,then the ratio of resultant intensities at these points will be

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

In a single slit diffraction pattern,the intensity and width of the fringes are:

"The person standing behind the open door inside the room can hear the voice of the person standing on the other side of the door but they cannot see each other". Give an experiment based on the diffraction for this statement.