Question

The slope of HGL will be

(a) greater than that of EGL for a pipe of uniform cross-section

(b) smaller than that of EGL for a pipe of uniform cross-section

(c) equal than that of EGL for a pipe of uniform cross-section

(d) independent of that of EGL for a pipe of uniform cross-section

I had been asked this question in an online interview.

My question comes from Hydraulic Gradient and Total Energy Line in portion Flow Through Pipes of Fluid Mechanics

Answer 1

The correct choice is (c) equal than that of EGL for a pipe of uniform cross-section

To explain: The vertical intercept between EGL and HGL is equal to the kinetic head. For a pipe of uniform cross-section, there will be no change in the velocity of flow across the pipe. Since the kinetic head remian constant, the slope of HGL will be equal than that of EGL.