Answer:
the diameter of the stand pipe is 24.456mm
Step-by-step explanation:
Given that:
Height of the soil sample = 90 mm
Cross section area of the soil sample = 6000 m²
The head fell from 500 mm to 300 mm
i,e


Time = 1500 s
The permeability of the soil (K) was 2.4x10⁻³ mm/s.
The objective is to determine the diameter of the stand pipe. (in mm)
Using the formula :




21600 = 45.983 a
a = 21600/45.983
a = 469.74 mm
Recall thar:
a = π/4 (d²)
So;
469.74 = 0.7854 ((d²)
d² = 469.74/0.7854
d² = 598.09
d = √598.09
d = 24.456 mm
Hence ; the diameter of the stand pipe is 24.456mm