2007-05-03 18:36:00 · 4 answers · asked by densphang 1 in Science & Mathematics ➔ Astronomy & Space
Rainbows have all the colors, but our eyes can only perceive those between ultraviolet and infrared. Thus, the spectrum we see is limited to those colors, with all the hues between them included.
2007-05-03 18:42:16 · answer #1 · answered by perudonations 3 · 0⤊ 0⤋
A rainbow is an optical and meteorological phenomenon that causes a "spectrum" of light to appear in the sky when the Sun shines onto droplets of moisture in the Earth's atmosphere.
The visible spectrum (or sometimes optical spectrum) is the portion of the electromagnetic spectrum that is visible to (can be detected by) the human eye. Electromagnetic radiation in this range of wavelengths is called visible light or simply light. There are no exact bounds to the visible spectrum; a typical human eye will respond to wavelengths in air from 400 to 700 nm, although some people may be able to perceive wavelengths from 380 to 780 nm. The corresponding wavelengths in water and other media are reduced by a factor equal to the refractive index. In terms of frequency, this corresponds to a band in the vicinity of 450-750 terahertz. A light-adapted eye typically has its maximum sensitivity at around 555 nm, in the green region of the optical spectrum. The spectrum does not, however, contain all the colors that the human eyes and brain can distinguish. Brown, pink, and magenta are absent, for example, because they need a mix of multiple wavelengths.
2007-05-03 18:53:40 · answer #2 · answered by Davy T 3 · 0⤊ 0⤋
Actually a rainbow has an infinite number of colors. The seven colors are actually just broad labels.
2007-05-03 18:49:47 · answer #3 · answered by pschroeter 5 · 1⤊ 0⤋
because there are only certain wavelengths our eyes can see.
we can only see from violet to red, but there is more to the spectrum that we cannot percieve.
check the site below for more info:
2007-05-03 18:44:28 · answer #4 · answered by anonymous knowledge-seeker 1 · 0⤊ 0⤋