Question

WHAT is spectrum?what is dispersion? WHAT is refractive index?

Answer 1

1.the set of colours formed on splitting of white light is called the spectrum of white light
2. the splitting of polychromatic light into its component colours on refraction is called dispersion of light
3.the ratio of the velocity of light in a vacuum to its velocity in a specified medium is refractive index

Answer 2

1.spectrum is the dispersion of white light into seven Colors(i.e. a rainbow)

2.dispersion is the spliting of light..

.......I hope it will help you