The slowest color, in the context of how light travels through a medium, is violet.
Explanation of Color and Speed
Light, as we perceive it, is composed of different colors, each corresponding to a specific wavelength. When light passes through a medium other than a vacuum (like air or glass), its speed changes. The degree to which the speed changes depends on the color's wavelength and the properties of the medium. This is quantified by the index of refraction.
- Index of Refraction: This is the ratio of the speed of light in a vacuum to its speed in a particular material. A higher index of refraction means the light travels slower in that material.
Violet's Slower Speed
Violet light has a shorter wavelength compared to other colors like red. Due to this shorter wavelength, violet light interacts more strongly with the atoms and molecules of the medium it's traveling through. This stronger interaction results in a higher index of refraction for violet light, meaning it slows down more than colors with longer wavelengths, such as red.
Think of it like this:
- Red light: A long, smooth car going over speed bumps. It barely notices them.
- Violet light: A short, bumpy car going over the same speed bumps. It gets jolted much more.
Because violet light is "jolted" more, it travels slower through a medium.
The Visible Spectrum Arrangement
This difference in speed is why when white light passes through a prism, it separates into the colors of the rainbow (the visible spectrum). Violet bends the most because it slows down the most, placing it at one end of the spectrum, while red bends the least and sits at the other end.
