(i) What is visible spectrum?
(ii) Why is red used as the stopping light at traffic signals?
(iii) Two triangular glass prisms are kept together connected through their rectangular side. A light beam is passed through one side of the combination. Will there be any dispersion? Justify your answer.
(i) Visible spectrum is the band of coloured components of a white light beam.
(ii) Red light is scattered the least by air molecules and has longer wavelength. It travels the longest distance.
(iii) The given setup will behave like a glass slab, resulting in recombination of the seven colours to produce white light.