Question

In the figure given alongside, a narrow beam of white light is shown to pass through a triangular glass prism. After passing through the prism, it produces a spectrum YX on the screen.
(a) State the colour seen (i) at X, and (ii) at Y.
(b) Why do different colours of white light bend through different angles with respect to the incident beam of light?
Figure.

Answer 1

(a) (i)The colour seen at X is violet (as it is the maximum deviated).
(ii) The colour seen at Y is red (as it is the least deviated).

(b) Different colours of white light bend at different angles with respect to the incident beam of light. This is because different colours have different wavelength.