List of top Water Resources Engineering Questions on Pipe networks

Consider the statements P, Q, and R.
P : Compacted fine-grained soils with flocculated structure have isotropic permeability.
Q : Phreatic surface/line is the line along which the pore water pressure is always maximum.
R : The piping phenomenon occurring below the dam foundation is typically known as blowout piping.
Which of the following option(s) is/are CORRECT ?

A 500 m long water distribution pipeline P with diameter 1.0 m, is used to convey 0.1 m³/s of flow. A new pipeline Q, with the same length and flow rate, is to replace P. The friction factors for P and Q are 0.04 and 0.01, respectively. The diameter of the pipeline Q (in meters) is ______ (rounded off to 2 decimal places).

A 2 m × 1.5 m tank of 6 m height is provided with a 100 mm diameter orifice at the center of its base. The orifice is plugged and the tank is filled up to 5 m height. Consider the average value of discharge coefficient as 0.6 and acceleration due to gravity (g) as 10 m/s². After unplugging the orifice, the time (in seconds) taken for the water level to drop from 5 m to 3.5 m under free discharge condition is _________ (rounded off to 2 decimal places).