Given below are two statements:
Statement I : Pressure of fluid is exerted only on a solid surface in contact as the fluid-pressure does not exist everywhere in a still fluid.
Statement II: Excess potential energy of the molecules on the surface of a liquid, when compared to interior, results in surface tension.
In the light of the above statements, choose the correct answer from the options given below.

Question

Given below are two statements:

Statement I : Pressure of fluid is exerted only on a solid surface in contact as the fluid-pressure does not exist everywhere in a still fluid.

Statement II: Excess potential energy of the molecules on the surface of a liquid, when compared to interior, results in surface tension.

In the light of the above statements, choose the correct answer from the options given below.

G1 Physics · Accepted Answer

Statement I is false. In a fluid at rest, pressure exists at every point in the fluid and acts in all directions. It is not restricted only to solid boundaries. Statement II is true. A molecule in the interior of a liquid is surrounded by neighbouring molecules in all directions, so the cohesive forces are approximately balanced. A molecule at the free surface has fewer neighbours above it and therefore possesses excess surface potential energy. This energetic tendency of the surface to reduce…