Hair of a shaving brush cling together when the brush is removed from water due to

The hairs of a shaving brush cling together when removed from water due to surface tension. While the brush is submerged, the hairs are surrounded by water and remain separated. However, as the brush is withdrawn, a thin film of water forms between the hairs. Surface tension acts to minimize the surface area of this liquid film, pulling the hairs toward each other to reduce the interface between the water and the air [t1][t6]. This phenomenon is a classic example of capillary attraction driven by the cohesive forces of water molecules, which are strong enough to keep particles close together [c2]. While viscosity affects the entrainment of fluid on hairy surfaces [t2][t3], the specific 'clinging' effect observed upon removal is primarily a result of surface tension attempting to contract the liquid surface.

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 7: Particulate Nature of Matter > 7.2.2 Liquid state > p. 105