Clouds float in the sky, why not fall? Because the cloud is light? Wrong, the clouds are actually not as light as you think, and the weight of the big clouds you see on weekdays is calculated in terms of "tons".
Some things seem to be very light, but they are actually very heavy, and clouds are such a typical example, you may not think of a cloud above your head, which can weigh up to 500 tons. Clouds are not only different in form, but also have many types, such as Cumulus clouds that often appear in humid coastal areas, altocumulus and cirrocumulus that often appear in the southern region in summer, cirratus and cirrus that are common in the north in winter, etc. The thickness of different clouds is different, so the difference in total weight is also very large, roughly speaking, the clouds we see on weekdays, if the length reaches one kilometer, the weight can reach about 500 tons.
Aren't one-kilometer-long clouds rare? No, a kilometer of clouds is very common and common.
Don't forget, clouds float in the sky, even the lowest-altitude Stratus clouds are 50 meters away from us, and most of the clouds are located in the area 600 to 4500 meters above the surface, while cirrus clouds that appear in southern China in summer can reach up to 10,000 meters or more. The cloud is so far away from us, so we see that the size of the cloud is very small, but in fact it may be very large, so an ordinary cloud in the sky is likely to be more than a kilometer long, which means that it weighs 500 tons. What is the concept of 500 tons? The weight of modern main battle tanks is about 50-70 tons, and one cloud is equivalent to ten main battle tanks. But it's so heavy, why doesn't it fall?
To know why the cloud does not fall, first know how the cloud is formed.
Clouds are made up of a visible polymer floating in the air, which is small water droplets and Xiaoice crystals. The surface water is illuminated by the sun's rays, gradually heating up into water vapor drifting high into the air, as the altitude increases, the temperature becomes lower and lower, so that water molecules will gather around the particles in the air to form small water droplets or Xiaoice crystals, these small water droplets and Xiaoice crystals gather together to form clouds. Water vapor, small water droplets or Xiaoice crystals, aren't they all colorless and transparent? Why are the clouds we see white? And not only white, in addition to the common white clouds, but also dark clouds on thunderstorms, red clouds in the morning and evening, and occasional golden clouds.
The clouds themselves have no color, the color comes from the sunlight shining.
Clouds are made up of water droplets and ice crystals that reflect sunlight, so the clouds appear white. The density and thickness of rain clouds are very large, so the sunlight cannot penetrate the clouds, so the clouds we see are black clouds. In the early morning and evening, the angle of incidence of sunlight is very large, oblique light to penetrate a very thick atmosphere, and the atmosphere of water molecules and various impurities will cause the light to scatter, so the short-wave part of the light is scattered, and the long-wave part is not scattered much, what is the long-wave? It is orange-red light, so these long-wave rays of light shine on the clouds and dye the clouds red. Knowing how clouds are formed, we can talk about why clouds don't fall from the sky.
Although the total weight of the clouds is high, but the area is large and the density is low, so they cannot break through the updraft lift, so they float in the sky, and only when the density of the clouds becomes very large, when the updraft is too large to support them, they will fall from the sky in the form of small water droplets, so the earth will fall into the sky.
Although the water droplets fall from a very high place, but because of the role of air resistance, these water droplets will gradually deform in the process of falling, until the rupture decomposes into smaller water droplets, after the water droplets become smaller, the falling terminal speed also decreases, so the speed of the water droplets when they finally fall to the ground is very small, so it will not hurt or itch when they hit the body. We know that the clouds don't fall because of the updraft lifting, so where does the updraft come from?
The formation of updraft usually has three forms, one is thermal uplift, the ground is warmed by the sun, which makes the surface air heated and expanded, so that the updraft is formed.
The second case is called dynamic lifting, where the air flowing on the surface is forced to rise when it encounters obstacles, for example, when the air flow reaches the windward side of the mountain, it will climb upward due to the obstruction of the terrain, so the updraft is formed. The third case is the result of the simultaneous action of thermal uplift and dynamic uplift, for example, when a hot air meets a cold air, because the cold air density is high and the hot air density is low, the cold air will move downwards, and the hot air encountered with it can only be forced to lift, thus forming an updraft. Thanks to the presence of updrafts, clouds weighing up to 500 tons can float safely in the sky.