![]() A droplet with a high refractive index will help produce a rainbow with a smaller radius. ![]() A refractive index is the measure of how much a ray of light refracts (bends) as it passes from one medium to another-from air to water, for example. ![]() The radius of a rainbow is determined by the water droplets' refractive index. As this reflected light leaves the droplet, it is refracted again, at multiple angles. It is then reflected by the back of the droplet. Light entering a water droplet is refracted. A refracted wave may appear "bent," while a reflected wave might seem to "bounce back" from a surface or other wavefront. Both refraction and reflection are phenomena that involve a change in a wave's direction. Rainbows are the result of the refraction and reflection of light. In fact, the center of a primary rainbow is the antisolar point, the imaginary point exactly opposite the sun. The sun or other source of light is usually behind the person seeing the rainbow. The appearance of a rainbow depends on where you're standing and where the sun (or other source of light) is shining. Rainbows can also be viewed around fog, sea spray, or waterfalls.Ī rainbow is an optical illusion-it does not actually exist in a specific spot in the sky. The most familiar type rainbow is produced when sunlight strikes raindrops in front of a viewer at a precise angle (42 degrees). This is also why purple is only sometimes included when we talk about rainbow colors- the color traditionally most strongly associated with the word "purple" has a clear (cyclic, at least) ordering when we talk about hue, but shades of purple are as a rule less saturated than the color associated with "violet" (the bottom line of that color spectrum is even known as the "line of purple"), and so make less sense to talk about when we are talking about /actual rainbows/.Īnyway, long story short: rainbow color ordering is mostly decided by frequency (or wavelength frequency = 1/wavelength) and so they provide appropriate terms.A rainbow is a multicolored arc made by light striking water droplets. In the above diagram, you can see that the spectral colors are along the edge, with different wavelengths of light demarcated. In the context of colors more broadly, we consider colors to be more "colorful" the closer they are to being pure- in color spaces this is known as saturation, and the dominant light frequency is known as color hue. Now, rainbows aren't composed of spectral colors (water shenanigans), but it's close enough that we associate the colors. The primary thing that distinguishes them is the constituent wavelength of light. These are the colors you get if you shine a narrow laser into a prism- they are comprised for the most part of a narrow range of pure colors (the light is of a small range of wavelengths). Rainbows aren't composed of just any colors, though- no brown!- they approximate with some success what are known as spectral colors. Now, colloquially we often draw rainbows with a near-subset of those, but if we want to talk about the actual colors of the rainbow, they are continuous and infinite in number. The majority of people's eyes rely on three different types of color receptor to pick up color. This is related to couple of other influences as well (that I'm not qualified to speak of), but one big factor is that These colors are somewhat arbitrary, but there is a tendency among languages to prioritize certain color groupings. In English, we have more or less eleven color terms that we would consider other colors to be instances of: 'black', 'white', 'red', 'green', 'yellow', 'blue', 'brown', 'orange', 'pink', 'purple', and 'grey'. for both directions: potentially spectral, spectrally ordered, or hue-ordered, although that last one is a little more ambiguous depending on whether you consider using blends of red and violet to transition between them appropriate for rainbow ordering.for the violet-red direction, antifrequential, antifrequentially ordered, or wavelength-ordered.for the red-violet direction, frequential or frequentially ordered.
0 Comments
Leave a Reply. |