Question

The formula for the open-end test is given by _________

(a) \(k=\frac{q}{5.5rh} \)

(b) \(k=\frac{5.5rh}{q} \)

(c) \(k=\frac{q}{5rh} \)

(d) \(k=\frac{q}{0.5rh} \)

The question was posed to me during an internship interview.

I'd like to ask this question from Well Hydraulics in portion Well Hydraulics of Geotechnical Engineering I

Answer 1

The correct answer is (a) \(k=\frac{q}{5.5rh} \)

Easiest explanation: The permeability can be calculated from,

\(k=\frac{q}{5.5rh}\) where k=permeability

q=discharge or constant rate of flow

r=radius of casing

h=differential head of water.