Question

What happens if the dispersion of the light does not take place?

Answer 1

if dispersion of light does not take place then the solution is true solution.

Answer 2

The breaking of light into its seven constituents is known as Dispersion.  The reason for the Dispersion is varying wavelength of white light

If one optically prevents the natural dispersion of light from a given source of light, then we obtain a near parallel beam.

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