Capillarity is due to

Question

Question

This question was previously asked in

WBPSC JE Mechanical 2018 Official Paper

Answer 1

Concept:

Capillarity:

If a tube of the very narrow bore (called capillary) is dipped in a liquid, it is found that the liquid in the capillary either ascends or descends relative to the surrounding liquid. This phenomenon is called capillarity.

MPL Quiz jayesh sah D1

The root cause of capillarity is the difference in pressures on two sides of (concave and convex) curved surface of the liquid.

EXPLANATION:

The property of the surface of a liquid that allows it to resist an external force is due to the cohesive nature of its molecules.

The cohesive forces between liquid molecules are responsible for the phenomenon known as surface tension.
Capillary action occurs because water molecules bond each other strongly due to forces of cohesion and adhesion where water molecules are attracted and stick to other substances such as glass or paper.