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Why do shorter wavelengths of light bend more than longer wavelengths in a prism?

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A circular RYB color wheel divided into twelve segments, showing a progression of colors from red, orange, and yellow to green, blue, and violet. — colour The RYB color model is being illustrated on a color wheel.

The bending of light, known as refraction, occurs because light changes speed when passing from one medium to another, such as from air into a glass prism.

The degree to which light bends is determined by the refractive index of the material, which is defined as the ratio of the speed of light in a vacuum to its speed within the substance ( $n = c / v$ ). Because the speed of light in a transparent medium depends on its wavelength, different colors (wavelengths) experience different refractive indices.123

Shorter wavelengths, such as those toward the violet end of the spectrum, travel more slowly in the medium than longer wavelengths, such as those toward the red end. Consequently, shorter wavelengths are refracted—or bent—more significantly than longer wavelengths. This phenomenon, where light is separated into its constituent colors due to wavelength-dependent velocities, is known as dispersion.4