Question

A glass slab is able to produce a spectrum when light passes through it but a glass slab does not produce any spectrum . Explain why it is so?

Answer 1

• A glass prism can form spectrum of colours with incidence of light on it due to refraction of light.
• In the case of glass slab, it can be treated as combination of two glass prism in opposite direction.
• The spectrum of colours formed by first prism in the glass slab are mixed again in the second prism to form white light. So, there is no spectrum from glass slab.