Why Are Rainbows Colorful?
Rainbows are colorful because water droplets in the atmosphere act like tiny prisms, separating sunlight into its component colors.
Sunlight appears white to us, but it's actually made up of all the colors of the rainbow. When sunlight enters a raindrop, it slows down and bends (this is called refraction). Because different colors of light have slightly different wavelengths, they bend at slightly different angles. This separates the white light into its constituent colors – red, orange, yellow, green, blue, indigo, and violet. The light then reflects off the back of the raindrop and bends again as it exits, further separating the colors. This separated light is what we see as a rainbow. Canon Science Lab | How Do Rainbows Form? explains this process clearly.
The commonly held belief that rainbows have seven colors stems from Isaac Newton's work, who significantly advanced our understanding of light. ELI5: Why are the colours in rainbows in separate lines?
The colors in a rainbow actually overlap at their edges, creating a brighter, almost white area inside the arc. Rainbow
The Role of Wavelengths
The colors we perceive are a result of light being split into its various individual wavelengths. This produces a spectrum of colors. What are the colours of the rainbow? - Met Office Each color corresponds to a specific wavelength: red has the longest wavelength, while violet has the shortest.
Light's Journey Through a Raindrop
- Sunlight enters a raindrop.
- The light refracts (bends) as it slows down.
- Different wavelengths (colors) bend at slightly different angles.
- The light reflects off the back of the raindrop.
- The light refracts again as it exits the raindrop.
- The separated colors are visible as a rainbow to the observer. What Causes a Rainbow? | NOAA SciJinks – All About Weather
This process is similar to how light is separated when passing through a prism. visible light - Why isn't the sunset/sunrise rainbow-colored - Physics ...
