(a) Why do spectrum colours recombine on passing through two prisms oriented duly ?
(b) What is the essential condition for observing a rainbow ?

what is a rainbow ? What is the essential condition for observing it ?

Why do different colours deviate through different angles on passing through a prism ?

Why do you not see a spectrum of colours when light passes through a flat pane of glass ?

In the spectrum of white light through the prism, which colour is seen at the top and why ?

A student observes the above phenomenon in the lab as a white light passes through a prism. Among many other colours, he observed the position of the two colours Red and Violet. What is the phenomenon called? What is the reason for the violet light to bend more than the red light?

Two beams of red and violet colours are made to pass separately through a prism (angle of the prism is 60degree ). In the position of minimum deviation, the angle of refraction will be