Question

Why rains fall slowly and continue so long time why don't the rain droplets fall in once ?​

Answer 1

Answer:

It is very simple. Let me start from the clouds. Many think cloud is water vapor but actually, it is a mass of tinny water droplets. These water droplets are pulled by the gravity but remain floating due to the buoyancy of the air. Now, with convection, the cloud moves up and the tinny water drops collide with each other,generating much bigger droplets. When droplets unite together, their weight increases so much that they are pulled by the gravity. When they are pulled by the gravity, they do not come in a straight line, rather due to wind and turbulence in air, their movement is chaotic. With the result, they collide with each other and break into new droplets. Also, due to the surface tension of water, only droplets up to about 2 mm or so are able to remain in spherical shape and beyond that they are oblate. The horizontal size is much more than the vertical size. The downward motion is opposed by the wind.

Thanks to nature that rain comes by striking each other otherwise, nothing would have survived on earth, if a raindrop of just 5 mm in diameter was coming straight from the cloud height say just 2 km above the surface of earth. For those who wish to know that the maximum terminal velocity of raindrops is < 10 m/s. Please calculate the velocity if the drop was coming from a height of 2 km? Also, thanks to nature, even if we throw a bucket of water at cloud height, it will get fragmented into millions of droplets for the benefit of entire ecosystem on earth.

Explanation:

Hope it helps you