GATE CE 2021: Soil Mechanics & Foundation Engineering#12 (App update required to attempt this test)

Steady pumping of a well at 314 m³/hour produces drawdowns 4.0 m and 2.0 m at radial distances 2.0 m and 20.0 m respectively in a confined aquifer. The transmissivity of the aquifer is about:

A confined aquifer of 15 m constant thickness is sandwiched between two aquicludes as shown in the figure (not drawn to scale)

The heads indicated by two piezometers P and Q are 55.2 m and 34.1 m, respectively. The aquifer has a hydraulic conductivity of 80 m/ day and its effective porosity is 0.25. If the distance between the piezometers is 2500 m, the time taken by the water to travel through the aquifer from piezometer location P to Q (in days, round off to 1 decimal place) is ______.

Water table of an aquifer drops by 100 cm over an area of 1000 km2. The porosity and specific retention of the aquifer material are 25% and 5%, respectively. The amount of water (expressed in km³) drained out from the area is ______ .

The interstices in a clay are of size equal to one tenth of the mean diameter of the grain. The height to which water will rise in the clay soil of average grain diameter 0.10 mm is _______ m.
[Assume surface tension at air-water interface as 0.073 N/m]