A discussion of the coalescence of cloud droplets that is necessary for the formulation of rain at temperatures above freezing. Upon colliding, larger water drops are commonly observed to rebound without coalescing unless electrostatic fields are present. This paper uses a theoretical solution by Dr. M. H. Davis for the force and field between two equal conducting spheres in a uniform field to compute the forces and fields between neighboring cloud droplets. The results explain the observed electrostatic coalescence.
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