78.

79.

80.

81.

82.

83.

109/23

In a drip irrigation system, organic matter or algae can be removed by using the
A) Sand media filter B) Screen filter
C) Centrifugal separator D) Disc filter

The soil sample of a field when tested shows EC of saturation extract with value
greater than 4.0 milli mhos/cm at 25°C, ESP value greater than 15 and pH of saturated
paste exceeds 8.5. Hence, soil is classified as

A) Alkali soil B) Saline soil

C) Saline-alkali soil D) Non saline soil

A centrifugal pump discharges 0.02 cubic metre of water per second against total
head of 40 m when the speed is 1450 rpm. The specific speed (rpm) of the pump is

A) 12.89 B) 12.19 C) 47.05 D) None of the above

Hydraulic resistance (days) is a characteristic of an semi confined aquifer representing
upward or downward leakage. If the value of hydraulic resistance attains Zero or
near to zero it would indicate as

A) Impervious layer B) Aquifer
C) Semi permeable aquifer D) None of the above

The most economical or the most efficient rectangular channel section can be
achieved subjected to condition that

A) Depth of flow (d) is half the bottom width

B) Its hydraulic radius is equal to half the depth of flow

C) Both A) and B)

D) Its hydraulic radius is equal to half the bottom width

In case of Theis Recovery method, the drawdowns in the pumped or nearby
observation well are measured at different time intervals during and after the pumping
is stopped. While estimating transmissivity (T) and storage coefficient (S) which of
the following statement is not valid ?
A) Storage coefficient (S) can be determined from the value of drawdown at the
time of pump stopped
B) Residual drawdown (s’) pertains to time elapsed for recovery
C) Residual drawdown (s’) pertains to time elapsed for both drawdown and recovery
D) Transmissivity (T) is directly proportional to drawdown difference per log cycle
of ratio of total time for both drawdown and recovery to recovery

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