For generations, schoolchildren have been taught that raindrops start as micro-droplets that then gather together in clouds with their neighbors to become bigger droplets.
Complex interaction between these droplets as they fall explains why raindrops come in such a remarkable range of sizes, goes this idea.
But French scientists armed with ultra-fast video footage say something else happens on the way down -- and this is why rainfall can range from fine droplets to chubby plops.
Initially, a raindrop starts to fall as a sphere, but then flattens out into a pancake shape.
Eventually, as the pancake widens and thins, the onrush of air causes it to hollow out, like an upturned bag.
The bag then inflates beyond the ability of the water's tension to hold things together and bursts into lots of smaller droplets.
From : Discovery Channel
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