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GATE questions from Hydrology - GATE PSUs preparation -part 10

Hi,
Here are few statements from Hydrology which has made their place in GATE Civil Engineering(CE). The bold letter represents the answer which are absent in actual question.


  1. A linear reservoir is one in which storage varies linearly with outflow rate.
  2. When there is an increase in the atmospheric pressure, the water level in a well penetrating in a confined aquifer does not undergo any change.
  3. During a 6-hour storm, rainfall intensity was 0.8 cm/hour on a catchment of area 8.6 km^2. The measured runoff volume during this period was 2,56,000 m^3. The total rainfall that was lost due to infiltration, evaporation, and transpiration (in cm/hour) is 0.304.
  4. Vertical hydraulic conductivity of the top soil at certain is 0.2 cm/hr. A storm of intensity 0.5 cm/hr occurs over the soil for an indefinite period. Assuming surface drainage to be adequate, infiltration rate after the storm has lasted for a very long time, shall be 0.2 cm/hr.
  5. While applying Rational formula for computing design discharge, the rainfall duration is stipulated as the time of concentration because this leads to the largest possible rainfall intensity.
  6. The plan area of a reservoir is 1 km^2. Water level in the reservoir is observed to decline by 20 cm in a certain period. During this period, the reservoir  receives a surface inflow of 10 hectares-meters, and 20 hectares-meters are abstracted from the reservoir for irrigation and power. The pan evaporation and rainfall recorded during the same period at a near by meteorological station are 12 cm and 3 cm respectively. The calibrated pan factor is 0.7. The seepage loss from the reservoir during this period in hectare-meters is 4.6.
to be contd...


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