Observe the given diagram and answer the questions :[Figure: a triangular glass prism; a beam of white “Sun light” falls on one face, is refracted inside the prism and comes out of the other face as a band of colours marked R, O, Y, G, B, I, V from t…

Answer: (a) Dispersion of light; (b) violet; (c) red; (d) rainbow; (e) the band of colours obtained on splitting white light.

(a) The splitting of white light into its seven constituent colours when it passes through a prism is called dispersion of light.

(b) Violet light has the shortest wavelength, so it is refracted (bent) the most and appears at the bottom of the band.

(c) Red light has the longest wavelength, so it is refracted the least and appears at the top of the band.

(d) The rainbow — sunlight is dispersed by tiny water droplets after rain.

(e) A spectrum is the band of seven colours (violet, indigo, blue, green, yellow, orange and red) obtained when white light is dispersed, arranged in order of increasing wavelength.