Why do rainbows sometimes appear after rain?

Because there will be many small water droplets in the air after rain, and the water droplets are like small prisms. When the sun shines on the water droplets in the air, the light is refracted and reflected and dispersed into red, orange, yellow, green, blue, indigo and purple, thus forming a rainbow that we can see. The bigger the water drop, the clearer the rainbow.

The reason why rainbows are all curved is also related to the bending degree of light when it passes through water droplets and the color of light. The curvature of red light is the largest, and that of violet light is the smallest. So the blue of the rainbow we often see is always below the red. If we are in the right place, we can also see a round rainbow.

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Poems related to the rainbow;

1, two water clips, double bridge falling rainbow. ? —? Qiu Dengxuan Xie Chengshu North Building by Li Bai, a poet in Tang Dynasty

Wanxi and Juxi surround Xuancheng like mirrors, while Phoenix and Jichuan Bridge fall into the world like rainbows.

2. On the first day of the incense burner, the waterfall sprayed Chen Hong. —? Meng Haoran, a poet in the Tang Dynasty, "Looking at Lushan Mountain in Li Peng Lake"

A red sun rises from the censer peak, and the waterfall reflects into a rainbow.

We will visit each other another day, and then climb the rainbow on the bridge. —? Li Bai, a poet in the Tang Dynasty, sent a message to the former residence of Huangshan White Goose Peak.

I will come to see it from time to time and take the bow bridge into the rainbow.

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