Lateral displacement increases with increase in angle of incidence and also increases with increase in refractive index. since refractive index increases with decrease in wavelength, so does lateral displacement, i.e, lateral displacement is more for violet light than for red.
(a) With the help of a diagram, show how when light falls obliquely on the side of a rectangular glass slab, the emergent ray is parallel to the incident ray. . (b) Show the lateral displacement of the ray on the diagram. (c) State two factors on which the lateral displacement of the emergent ray depends.