The formation of yuet
Most of China is a product of cumulus clouds. How did China come into being? China is formed by diffraction when light passes through water droplets or small ice crystals in clouds.
Diffraction is also called diffraction. Generally speaking, light travels in a straight line, but due to its fluctuation, when it encounters a tiny obstacle, the light wave will bypass its edge and reach the back of the obstacle, that is, deviate from the original straight line direction, and the degree of this deviation varies with the color of light. We can also see the diffraction phenomenon of light in our daily life. Put a feather between the eyes and the light, and look at the light through the gap of the feather, and you can see that there is a colorful halo around the light. This is because light is diffracted when it passes through tiny feather gaps. Also, if you breathe into the glass window, a water vapor film will form on the glass. At this time, if you look at a light source in the distance outside the window, you can see a colorful halo like China outside the light source.
Similarly, when the optical cable passes through small water droplets and small ice crystals in the cloud, it will also diffract and produce colorful halos-Hua.
The size and clarity of China are related to the structure of clouds. When the cloud is thick, diffracted light is not easy to pass through and glare is not easy to produce; When the clouds are thin, people can easily see China. If the size of water droplets and ice crystals in the cloud is relatively consistent, then the China ring is relatively complete; If the size of water droplets and ice crystals are different, the rings will be irregular and some parts will not be visible.
The size of China ring is inversely proportional to the size of water droplets and ice crystals in the cloud. The larger the water droplets and ice crystals are, the smaller the diameter of China ring is. The smaller the water droplets and ice crystals, the larger the diameter of China ring.
According to the change of the diameter of the central ring, the weather can be predicted. If the garland gradually expands, it means that the water droplets and ice crystals in the cloud have become smaller because of evaporation, so it won't rain, or it will be sunny.
If the diameter of the wreath is shrinking, it means that the water droplets and ice crystals in the clouds are gradually increasing, the clouds are gradually thickening, and the weather will turn rainy. Folks say, "Dahua is sunny, Xiaohua is rainy."