Light appears to travel in straight lines since

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

The phenomenon that explains why light waves do not travel in a straight line is known as .......

$A$ circular disc is placed in front of a narrow source. When the point of observation is at a distance of $1 \, m$ from the disc,the disc covers the first $HPZ$ (Half Period Zone). The intensity at this point is $I_0$. The intensity at a point at a distance of $25 \, cm$ from the disc will be:

In an experiment of single slit diffraction pattern,the first minimum for red light coincides with the first maximum of some other wavelength. If the wavelength of red light is $6600\,\mathring{A}$,then the wavelength of the first maximum will be.....$\mathring{A}$

Consider the diffraction pattern obtained from the sunlight incident on a pinhole of diameter $0.1 \, \mu m$. If the diameter of the pinhole is slightly increased,it will affect the diffraction pattern such that :