Question

Specific retention of groundwater is larger in coarse-grained soils.

(a) True

(b) False

The question was asked during an interview for a job.

The above asked question is from Aquifers and Their Type-1 in section Ground Water for Irrigation through Wells and Tubewells of Irrigation Engineering

Answer 1

Correct answer is (b) False

The best I can explain: Specific retention can be defined as the amount of water held between the grains due to molecular attraction on the walls of the interstices. If the effective size of grain decreases, the surface area between the interstices will increase causing more specific retention and less specific yield. In fine soils like clay, the specific retention would be more and it results in small specific yield.