Question

In falling head permeability test, change in the head at a time interval dt is denoted as ___________

(a) dh

(b) –dh

(c) h

(d) –h

I got this question in exam.

I would like to ask this question from Constant and Falling Head Permeability Test topic in section Permeability of Geotechnical Engineering I

Answer 1

Right option is (b) –dh

The best explanation: -dh is used to denote a change in a smaller time interval dt, the minus sign has been used since h decreases as t increases.