MCQ
1. A unit hydro graph has one unit of
Rainfall duration
Rainfall excess
Time base of direct runoff
Discharge
2. If ID is the depth of scour below original bed, then the width of launching apron is generally taken as
1.2 D
1.5 D
2.0 D
2.5 D
3. For efficient working of a control meter, its throat length is approximately kept
Equal to the critical depth
Twice the critical depth
Three times the critical depth
Four times the critical depth
4. In the estimate of design flood, Dickens assumes that high flood in cumecs, is proportional to catchment area raised to the power
1/4
1/2
3/4
2/3
5. Pick up the correct statement from the following:
If ground water enters the channel, the channel is known as effluent channel
If water goes out of channel to meet ground water, the channel is said to be influent stream
If the water table is at higher level than the water level in channel, ground water flows to the stream
All the above
6. The sensitivity of a rigid module is
Zero
Between zero and one
1
Infinity
7. Lining of irrigation channels
Increases the water-logging area
Decreases the water-logging area
Does not change the water logging ares
None of the above
8. Pick up the correct statement from the following:
The unit hydrograph of a specified unit duration obtained from the past data can be used to obtain the hydrograph of future storms of like duration
To obtain the ordinates of storm hydrograph, the ordinates of unit hydrograph are multiplied by the multiplying factor
The multiplying factor for storm hydrograph may be obtained by dividing the run off in mm by 25 mm
All the above
9. The net head under which the turbine reaches its peak efficiency at synchronous speed is called
Design head
Rated head
Gross head
Operating head
10. Discharge curve may be extended by logarithmic method if
Cross section of river is uniform
River is broader and shallower
River is of any type
None of these
11. Izzard formula for the time of concentration in minutes for the plots having no channels, is (where Lo is the length of overland flow in metres and Kp rainfall intensity in cm/hour)
T= 111 b. L0 1/3/(Kp)2/3
Т= 222 bL10 1/2/(Kp)1/3
T= 333 b. LO/Kp
T= 111 b. LO 1/3/(Kp)2/5
12. When the reservoir is full, the maximum compressive force in a gravity dam is produced
At the toe
At the heel
Within the middle third of base
At centre of base
13. When a constant discharge 2.91 litres/sec. was obtained in a pumping test, the draw downs in the test wells at 3 m and 6.184 m were 2.6 m and 0.3 m respectively. If over-all depth of the pumping well was 16 m, the permeability of the soil, is
0.0005 cm/sec
0.001 cm/sec
0.002 cm/sec
0.01 cm/sec
14. Pick up the correct statement from the following:
Yield of a drainage basin is the run off at any time
Yield of a drainage basin is the run off over long periods
Yield of a drainage basin is expressed as surface run off per year
Run off is expressed as total volume per day
15. Precipitation caused due to striking of air masses with a topographical feature, is called
Orographic precipitation
Convective precipitation
Cyclonic precipitation
None of these
16. Vertical drop fall is satisfactory for a height upto
0.5 m
1.5 m
3.5 m
5.0 m
17. For the upstream face of an earthen dam, the most adverse condition for stability of slope is
Sudden drawdown
Steady seepage
During construction
Sloughing of slope
18. The equation V (1000 ID10/60)×(1.8T+42) which is used for determining the velocity of ground water flow in metres per day is known as
Meinzer's formula
Slichter's formula
Darcy's formala
Hazen formula
19. An aggrading river is a
Silting river
Scouring river
Both silting and scouring river
Neither silting nor scouring river
20. The stage of river carrying a discharge of Q m/sec at a point is 10 m and slope of water surface is (1/4000). The discharge of a flood same point and same stage of 10 m with a water surface slope of (1/1000) will be
3/sec
0.5 Q m3/sec
2 Q m3/sec
4 Q m3 sec