Question

During seepage through an earthen mass, the direction of seepage is ________________ to the equipotential lines.

(a) perpendicular

(b) parallel

(c) not defined

(d) diagonal

The question was posed to me during a job interview.

I want to ask this question from Design Criteria of Earth Dams topic in portion Earthen and Rock Fill Dams of Irrigation Engineering

Answer 1

Correct answer is (a) perpendicular

The explanation: The seepage through a pervious soil material for 2-D flow is given by Laplacian equation and the graphical solution suggests that the flow through the soil can be represented by flow-net. It consists of 2 sets of curves equipotential line and streamlines which is mutually perpendicular to each other.