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Small drops of a liquid are spherical while large drops are elliptical .Explain ?

A small drop of mercury is spherical because the gravitational force on it is very small and the liquid shape is then mainly due to surface tension forces. Although the density of mercury is high, small drops of mercury are spherical. The ratio of surface area (4?r²) to weight (or 4?r³/3) of a sphere is proportional to the ratio r²/r³ or 1/r. Thus, the smaller the radius, the greater is the influence of surface tension forces compared with the weight. However, large mercury drops are flattened on top. This time the gravitational force is relatively greater.