Question

If the sub-soil formation is of fine sand, the rough value of the specific yield of well per unit area of the well (K/A) given by Marriot is ____________

(a) 0.25

(b) 0.50

(c) 0.75

(d) 1.0

This question was addressed to me during an internship interview.

This interesting question is from Open Well and Dug Well in chapter Ground Water for Irrigation through Wells and Tubewells of Irrigation Engineering

Answer 1

The correct choice is (b) 0.50

The best explanation: When the limit of critical velocity is not exceeded it may be rightly assumed that K/A is constant for a well. K/A is the specific yield of well per unit area of the well. The value for K/A given by Marriot for clay sub-soil is 0.25, for fine sand = 0.50 and for coarse sand, it is 1.0.