For the visibility of a diffraction pattern of a wave of light,the size of the slit or obstacle should be

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

In the diffraction pattern of a single slit,the width of the secondary maxima compared to the central maximum is:

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 $D=$

In a diffraction experiment from a single slit, the angular width of the central maxima does $NOT$ depend upon

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?