How does dispersion occur in a prism?

Dispersion in a prism occurs because different colors (wavelengths) of light bend by different amounts when they pass through the prism material. Here’s how it works:

1. White light is made up of many colors, each with a different wavelength.
2. When white light enters the prism, it slows down and bends (refracts) because the prism’s glass is denser than air.
3. The amount of bending depends on the wavelength: shorter wavelengths (like blue and violet) bend more than longer wavelengths (like red).
4. As a result, the light separates into its component colors inside the prism.
5. When the light exits the prism, the colors spread out further, forming a visible spectrum from red to violet.

So, dispersion is the splitting of white light into a spectrum of colors due to the wavelength-dependent bending (refraction) inside the prism. This is why a prism creates a rainbow-like band of colors.