The scientific name for the separation of white light into its different colours when it passes through a prism is dispersion of light.

Quick Scoop

When a beam of white light enters a glass prism, each colour in the light bends by a slightly different amount because each wavelength has a different refractive index in the glass.

This unequal bending spreads the colours out into a visible spectrum (VIBGYOR: violet, indigo, blue, green, yellow, orange, red), and that phenomenon is called dispersion of light.

A Tiny Story To Remember It

Imagine white light as a group of runners all starting together but each running at a slightly different speed on a track that curves.

The prism is like that curved track: because each “runner” (colour) travels differently in the glass, they spread out, and your eye sees them as a fan of separate colours — this spreading out is dispersion.

So if a question asks: “What is the scientific name for the separation of light into its different colours when it passes through a prism?”
The one-word answer you want is: Dispersion.

TL;DR: The separation of light into colours by a prism is called dispersion of light.

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