Question

Will a glass slab also form a spectrum like a prism?Explain

Answer 1

No.... a glass slab won't form a spectrum like prism..... because in the glass slab... the glass surfaces are parallel to each other.... but in prism.... the glass surfaces are inclined at a particular angle........................... :)

Answer 2

No, a glass slab will not form a spectrum like prism. This is because the opposite faces of a glass slab a parellal to each other. So, the emergent and incident say will be parellal and dispersion won't happen.
A prism forms spectrum because of it's shape. The opposite faces are not parellal and during refraction , the white light ray splits into it's constituent colours and spectrum is formed.