Metal paperclip is held on water by surface tension
Molecules of a liquid experience
mutual attraction forces. Inside the liquid, the attraction forces of other molecules act on all sides and therefore cancel each other out. Molecules on the surface of the liquid have no neighbors on the outside, and the resulting attraction force is directed inside the liquid. As a result, the entire water surface tends to shrink under the action of these forces.
Cumulatively, this effect leads to the formation of the so-called
surface tension force, which acts along the liquid surface and results in the formation of a semblance of an invisible, thin and elastic film on it.
