Why are drops of liquid always spherical in shape?

Every molecule of liquid draws its neighboring molecules towards it, and is itself also drawn towards every neighboring molecule. Only the molecules which are on the surface are not drawn externally. Beyond the surface there are no further molecules, hence obviously there is no question of being pulled by other molecules in the outward direction. Result: Every molecule on the surface faces equal pull inward. It is as if the common center in the liquid is exerting equal pull on each of the molecules and drawing them towards it. Thus, liquid naturally takes spherical shape and a droplet is formed. Albeit, not necessarily every droplet is a perfect sphere. The form ultimately depends on the size of a droplet. For example, below picture shows droplets of mercury.

The first one is a perfect sphere because every droplet “tries” to keep the surface area to the minimum. As the drops get bigger they are flattened out. Due to large size the pull between the molecules is not enough to hold them together strongly. The same applies to water droplets as well, which we see sliding on the leaves of plants without wetting the surface.

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