The bending of a beam of light around the corners of obstacles is called

$A$ parallel beam of monochromatic light of wavelength $5000 \; \mathring{A}$ is incident normally on a single narrow slit of width $0.001 \; mm$. The light is focused by a convex lens on a screen placed on the focal plane. The first minimum will be formed for the angle of diffraction equal to ........$^o$.

Light appears to travel in straight lines since

In a single slit diffraction pattern,if the first maxima of light of wavelength $\lambda$ coincides with the first minima of yellow light $(540 \ nm)$,then $\lambda$ is ......... $nm$.

Assertion : Standard optical diffraction gratings cannot be used for discriminating between $X-$ray wavelengths.
Reason : The grating spacing is not of the order of $X-$ray wavelengths.

$A$ diffraction pattern is obtained by making blue light incident on a narrow slit. If blue light is replaced by red light,then: