Refraction through a Rectangular Glass Slab

Why is there no dispersion of light refracted through a rectangular glass slab ?

Assertion: There is no dispersion of light refracted through a rectangular glass slab. Reason : Dispersion of light is the phenomenon of splitting of a beam of white light into its constituent colours.

Assertion : There is no dispersion of light refracted through a rectangular glass slab. Reason : Dispersion of light is the phenomenon of splitting of a beam of white light into its constituent colours.

Refraction Of Light Through Rectangular Glass Block

A student traces the path of a ray of light passing through a rectangular glass. Slab. For measuring the angle of incidence, he must position the protractor in the manner shown in figure :

Amol performed an experiment on tracing the path of a ray of light passing through a rectangular glass slab. When ray of light enters from air to glass slab, he observed angle I =45^(@) . The angle of refraction must be