The rise or fall of a liquid inside a tube of very small bore when dipped in a liquid is known as capillarity. Which fundamental force primarily drives this phenomenon?

💡 Solution & Explanation

Capillarity is driven by the interplay between cohesive forces among liquid molecules and adhesive forces between the liquid and the solid container walls, mediated by surface tension. When adhesion exceeds cohesion, the liquid wets the surface and rises within narrow tubes. The ascent of sap in tall trees through xylem vessels relies significantly on capillary action and transpiration pull.