Question

When does surface Tension in the water become zero?

(a) When the soil is completely dried

(b) When the soil is fully saturated

(c) When the water evaporates

(d) None of the mentioned

I got this question in semester exam.

The origin of the question is Shrinkage and Swelling of Soil topic in division Soil Water Effective and Neutral Stresses of Geotechnical Engineering I

Answer 1

Correct answer is (b) When the soil is fully saturated

Easy explanation: Initially when the soil is fully saturated, the capillary space between the particles are completely filled with water, therefore the tension in the water becomes zero at this stage.