Kelvins Secret Dropper
The physics of Kelvin’s dropper is still not completely understood, since it is unclear how neutral drops of water, even when polarized, can acquire a unitary charge. The article suggests that the process of acquiring a unitary charge by droplets in a Kelvin dropper is similar to acquiring charges by raindrops falling from a thundercloud. Therefore, a thundercloud, judging by the physical processes occurring in it, represents a giant Kelvin dropper.