MCQ
61. As compared to gravity dams, earthen dams
Are costlier
Are less susceptible to failure
Require sound rock foundations
Require less skilled labour
62. The aqueduct or super-passage type of works are generally used when
High flood drainage discharge is small
High flood drainage discharge is large and short lived
High flood drainage discharge is large and continues for a long time
None of the above
63. method requires the following data pertaining annual flood series (1) Mean value (ii) Standard deviation (iii) Length of record (iv) Coefficient of skew The correct answer is
(i) and (ii)
(i) (i) and (iii)
(i), (ii) and (iv)
(i), (ii), (int) and (iv)
64. For a proportional outlet, the flexibility is
Zero
Between zero and 1
1
Greater than 1
65. From the Survey of India map, the distance of the critical point is 20 km and difference in elevation is 193 m. The over land flow time, is
2 hours
3 hours
2 hours and 30 minutes
4 hours
66. Silt excluders are constructed on the
River bed upstream of head regulator
River bed downstream of head regulator
Canal bed upstream of head regulator
Canal bed downstream of head regulator
67. A river training work is generally required when the river is
Aggrading type
Degrading type
Meandering type
Both (A) and (B)
68. The maximum average depth due to one day storm over an area of 100 km² is 100 mm. DepthArea- Duration (DAD) curves indicate the same area of 100 km³ the maximum average depth for a 3 hour storm will be
100 mm
More than 100 mm
Less than 100 mm
None of the above
69. Non-recording rain gauges
Collect the rain whose volume is measured by means of graduated cylinders
Collect the rain which is directly measured by means of graduated cylinders in centimetres of water depth
Collect the rain which is directly measured by means of graduated cylinders in centimetres of water depth
Are cylindrical in shape
70. h flood estimate, is useful only for the catchments in
Southern India
Northern India
Eastern India
Western India
71. Pick up the correct statement from the following:
Perched aquifer is found in unconfined aquifer
The top surface of the water held in the perched aquifer, is known as perched water table
Perched aquifer is formed in unfined acquirer if an impervious layer exists
All the above
72. The uplift pressure on a dam can be controlled by (i) Constructing cut-off under upstream face (ii) Constructing drainage channels between the dam and its foundation (iii) By pressure grouting in foundation The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
(1), (ii) and (iii)
73. Pick up the correct statement from the following:
Rivers, lakes, oceans and springs get water from the rains
Rain water is obtained by evaporation from rivers, lakes and oceans
Water remains in atmosphere as vapours
All the above
74. In case of non-availability of space due to topography, the most suitable spillway is
Straight drop spillway
Shaft spillway
Chute spillway
Ogee spillway
75. From the pattern of the rainfall shown in the below figure, the total precipitation is
4 cm
4.5 cm
5 cm
5.5 cm
76. . If a gauge is installed perpendicular to the slope, its measurement is reduced by multiplying
Sine of the angle of inclination with vertical
Cosine of the angle of inclination with vertical
Tangent of the angle of inclination with vertical
Calibration coefficient of
77. The elevation Z of the watershed is: (where letters carry their usual meanings)
Reduced level of the top most point of the basin
Reduced level of the lower most point of the basin
Average elevation of the highest and lowest point of the drainage basin
Obtained by the formula Z=+++anzn)/A
78. The radius of influence is-
Radius of the main well
Distance from the wall of main well to the point of zero draw down
Distance from the centre of main well to the point of zero draw down
None of these
79. The stream which does not have any base flow contribution is called
Perennial stream
Intermittent stream
Ephemeral stream
None of the above
80. Pick up the correct statement from the following:
The portion of pellicular water which remains unutilised, is called hygroscopic, water
The moisture content at which permanent wilting of plants takes place, is called the wilting point
The moisture deficiency will be different at different points
All the above