Final answer:
A small drop of liquid tends to assume a spherical shape due to cohesive forces, while larger drops are less spherical. The roundness of drops is also influenced by the balance between cohesive and adhesive forces.
Step-by-step explanation:
A small drop of liquid tends to assume a spherical shape because a sphere has the smallest possible surface area for a given volume. This is due to the cohesive forces that hold the liquid molecules together. Larger drops, on the other hand, are less spherical because they are more affected by gravity, air resistance, and surface interactions.
When it comes to adhesion, if the cohesive forces within a liquid are stronger than the adhesive forces between the liquid and another substance, the liquid tends to keep to itself and form droplets. However, if the adhesive forces between the liquid and another substance are stronger than the cohesive forces, the liquid will spread out over the other substance.