Question

why does a prism disperse light into its 7 constituents while a plain glass slab doesn't

Answer 1

Prism disperse light into seven colour but the glass slab doesn't because Every light has different wavelength and when enters in the prism it dispers but a glass stab is vonsist of two prism when light ray enters in it it disperse into 7 colours and the second prism converse all the rays into one single ray.