Why are rainbows seven colored? Why is the rainbow seven colored?

The main wavelength range of visible light is about 390-700nm, and the naked eye has a distinction of about 40nm for the significant difference between the two colors, and the characteristic wavelength of the seven colors is as follows: red 650nm orange 610nm yellow 570nm green 530nm cyan blue 490nm blue indigo 450nm violet 410nm People often ask why there are "red, orange, yellow, green, blue, blue, violet" and "red, orange, yellow, green, blue, indigo", which is more accurate, in fact, both have their own truth, The above theory can give a better explanation. Newton's theory is "red-orange-yellow-green-blue-indigo", which is more biased towards 490nm, while the blue in "red-orange-yellow-green-blue-violet" is more biased towards 450nm.

The blue in the three primary colors of physics is also the blue that is accepted by more people, in fact, it is in between, roughly around 470nm. In the field of atmospheric science, there is a "tricolor absorption photometer" (tricolor absorption photometer), which is used to measure the light absorption of aerosols in the red, green and blue bands, and its three characteristic wavelengths are set to 652nm, 528nm and 467nm, which also confirms the above definition of red, green and blue. Water vapor molecules in the atmosphere refract sunlight and break it down into light waves of different wavelengths (i.e., different colors of light).

Newton deduced from the dispersion experiment with a prism that sunlight (white light) is a mixture of seven colors of light. The rainbow we see is not necessarily a seven-color rainbow, the rainbow at sunrise and sunset is red, while the blue and green rainbow is barely visible in the sky, and sometimes the rainbow is missing one or two colors for various reasons. Moreover, the colors of the rainbow are only recognized by the human eye, and we define the colors that can be seen and distinguished by the naked eye as seven (red, orange, yellow, green, blue, purple).

In fact, there are countless colors that transition from red to purple, but people can accurately express what color is. <>

A rainbow is an optical phenomenon in meteorology. When sunlight hits raindrops in mid-air, the rays are refracted and reflected, forming an arched spectrum of colors across the sky. The rainbow of colorful colors, from the outside to the inside, are:

Red, orange, yellow, green, cyan, blue, purple. Principle: The dispersion of light sunlight (white light) is composed of a variety of other lights, different wavelengths of light, and therefore different refractive indices when passing through the prism.

Red light has a long wavelength and a small refractive index; Violet light has a short wavelength and a large refractive index. Therefore, when a beam of light passes through the prism, it will turn red from top to bottom... Purple. After the rain, there will be a lot of small water droplets in the sky, and these small water droplets will play the role of a prism, and the rainbow will be produced, of course, it is related to some other factors, but the principle is the dispersion of light, and the refraction of light is 7 colors arranged in order according to the size of the wavelength.

Rainbows are colorful because the sunlight hits the air and closes to a spherical shape, causing dispersion and reflection.

The sunlight we see is composed of seven colors: red, orange, yellow, green, blue, indigo, and violet.

Because water has a dispersive effect on light, the refractive index of light at different frequencies is different, the refractive index of red light is smaller than that of blue light, and the deflection angle of blue light is larger than that of red light.

When sunlight hits a water droplet, it is incident at different angles at the same time, and it is reflected at different angles within the water droplet. The reflection of 40 to 42 degrees is the most intense, resulting in the rainbow we see. To cause this reflection, sunlight enters the water droplet, first refracts once, then reflects on the back of the droplet, and finally refracts again when it leaves the droplet, for a total of two refractions after one reflection.

Because water has a dispersive effect on light, the refractive index of light at different frequencies is different, the refractive index of red light is smaller than that of blue light, and the deflection angle of blue light is greater than that of red light. Because the light is reflected within the water droplet, the macro limb spectrum seen by the observer is reversed, with red light at the top and other colors at the bottom.

Refer to Encyclopedia - Rainbow.

Rainbow is a natural phenomenon caused by the reflection and refraction of light from the water droplets that hit the air.

We know that when sunlight passes through the prism, the direction of travel is deflected, and the original white light is broken down into bands of red, orange, yellow, green, blue, indigo, and violet. When it rains, or after rain, the air is filled with countless tiny droplets that can deflect the sun. When sunlight passes through water droplets, it not only changes the direction of travel, but is also decomposed into red, orange, yellow, green, blue, indigo, violet and other colors.

If the angle is right, it becomes the rainbow we see. Generally speaking, rainbows are only found in summer, because there are many showers in summer, and sometimes the sun slips in the east and shudders in the west, and the rain is not large. Winters are cold and dry, with little rain, and snowfall does not form rainbows.

1. The most common expression for the seven colors of light in East Asia and China is (from the outside to the inside): red, orange, yellow, green, blue, indigo, and violet. Rainbow, red, orange, yellow, green, blue, purple, also known as rainbow, referred to as rainbow, is an optical phenomenon in meteorology.

When sunlight hits water droplets in the air, the light rays are refracted and reflected, forming an arched multicolored spectrum across the sky, which is common after rain. The shape is curved and the colors are gorgeous.

2. Rainbow, also known as Tiangong (Hakka), Tianhong, Jiang, etc., referred to as rainbow, is an optical phenomenon in meteorology, when the sunlight shines on the water droplets in mid-air, the light is refracted and reflected, forming an arched colorful spectrum on the sky. In fact, the rainbow comes in an infinite number of colors, for example, there are many subtle colors between red and orange, but for the sake of simplicity, only seven colors are used as a difference.