irrigation water resources engineering and hydrology MCQs – Page 2

Practise focused irrigation water resources engineering and hydrology questions with marked answers for exam preparation and subject revision.

irrigation water resources engineering and hydrology Mcqs
51. The ratio of the average load to the installed capacity of the plant whose reserve capacity is zero will be equal to__________________?
comments icon0

A. load factor

B. plant factor

C. utilisation factor

D. both (A) and (B)

52. The ratio of average values of shear stresses produced on the bed and the banks of a channel due to flowing water is________________?
comments icon0

A. equal to 1

B. equal to zero

C. less than 1

D. greater than 1
53. An artesian aquifer is the one where______________?
comments icon0

A. none of the above

B. water is under pressure between two impervious strata

C. water table serves as upper surface of zone of saturation

D. water surface under the ground is at atmospheric pressure

54. If the intensity of rainfall is more than the infiltration capacity of soil, then the infiltration rate will be______________?
comments icon0
A. equal to infiltration capacity

B. more than infiltration capacity

C. equal to rate of rainfall

D. more than rate of rainfall

55. An aggrading river is a_________________?
comments icon0
A. silting river

B. scouring river

C. both silting and scouring river

D. neither silting nor scouring river

56. A 6 hours storm had 4 cm of rainfall and the resulting runoff was 2 cm. If <j) index remains at the same value, the runoff due to 10 cm of rainfall in 12 hours in the catchment is___________________?
comments icon0

A. 7.5 cm

B. 6.0 cm

C. 9.0 cm

D. 4.5 cm

57. The uplift pressure on the face of a drainage gallery in a dam is taken as_________________?
comments icon0

A. average of hydrostatic pressure at toe and heel

B. two-third of hydrostatic pressure at toe plus one-third of hydrostatic pressure at heel

C. none of the above

D. hydrostatic pressure at toe

58. A repelling groyne is aligned________________?
comments icon0

A. pointing downstream

B. parallel to bank

C. perpendicular to bank

D. pointing upstream
59. Assertion A : To estimate the rainfall over a catchment, the number of raingauges required per unit area is large for hilly areas. Reason R : Rainfall gradient is steep. Select your correct answer according to the coding system given below ?
comments icon0
A. Both A and R are true and R is the correct explanation of A

B. Both A and R are true but R is not the correct explanation of A

C. A is true but R is false

D. A is false but R is true

60. The most suitable material for the central impervious core of a zoned embankment type dam is_______________?
comments icon0
A. clay mixed with fine sand

B. coarse sand

C. clay

D. silty clay

61. A land is known as waterlogged_________________?
comments icon0

A. none of the above

B. when gravity drainage has ceased

C. capillary fringe reaches the root zone of plants

D. when the permanent wilting point is reached

62. The normal annual precipitation at stations X, A, B and C are 700 mm, 1000 mm, 900 mm and 800 mm respectively. If the storm precipitation at three station A, B and C were 100 mm, 90 mm and 80 mm respectively, then the storm precipitation for station X will be___________________?
comments icon0

A. 90 mm

B. 105 mm

C. 80mm

D. 70mm
63. The uplift pressure on a dam can be controlled by_________________?
comments icon0
A. constructing cutoff under upstream face

B. constructing drainage channels bet-ween the dam and its foundation

C. by pressure grouting in foundation</strong>

D. corret answer is?

E. only (1)

F. both (1) and (2)

64. If d is the depth of the aquifer through which water is flowing, then the relationship between permeability k and transmissible T is given by_______________?
comments icon0
A. T = kd

B. T = k/d

C. k= VTd

D. T= Vkd

65. Under the same conditions, which of the following shapes of water surface will give the highest rate of evaporation ?
comments icon0
A. convex water surface

B. flat water surface

C. concave water surface

D. independent of shape of water surface

66. The total capacity of a reservoir is 25 million cubic metres and dead storage is 5 million cubic metres. If the average volume of sediment deposition is 0.10 million cubic metre per year, then the usefulness of the reservoir will start reducing after_________________?
comments icon0

A. 200 years

B. 250 years

C. 50 years

D. 150 years

67. The major resisting force in a gravity dam is___________________?
comments icon0

A. wave pressure

B. uplift pressure

C. self-weight of dam

D. water pressure

68. Which of the following methods of applying water may be used on rolling land ?
comments icon0

A. furrow flooding

B. boarder flooding

C. check flooding

D. free flooding

69. Optimum depth of kor watering for rice is______________?
comments icon0

A. 135 mm

B. 165 mm

C. 215 mm

D. 190 mm
70. If the critical shear stress of a channel is xc, then the average value of shear stress required to move the grain on the bank is___________________?
comments icon0

A. 0.5 xc

B. 1.33 TC

C. 0.75 TC

D. xc

71. Study the following statements?
comments icon0

A. Spurs are constructed transverse to river flow</strong></span>

B. correct answer is

C. Levees are constructed transverse to river flow

D. Spurs are constructed parallel to river flow

E. ="color: #003f1a;">1. Levees are constructed parallel to river flow
72. The unit hydrograph of a specified duration can be used to evaluate the hydrograph of storms of_________________?
comments icon0

A. same and shorter duration

B. same duration only

C. same and longer duration

D. any duration
73. For a proportional outlet, the flexibility is______________?
comments icon0

A. between zero and 1

B. greater than 1

C. 1

D. zero

74. The minimum size of stone that will remain at rest in a channel of longitudinal slope S and hydraulic mean depth R is given by______________?
comments icon0

A. 15 RS

B. 11 RS

C. 7RS

D. 4RS

75. The flow of water after spilling over the weir crest in chute spillway and side channel spillway respectively are_________________?
comments icon0
A. at right angle and parallel to weir crest

B. parallel to weir crest in both

C. at right angle to weir crest in both

D. parallel and at right angle to weir crest

76. A unit hydro graph has one unit of_______________?
comments icon0

A. time base of direct runoff

B. rainfall excess

C. rainfall duration

D. discharge

77. The ratio of the quantity of water stored in the root zone of the crops to the quantity of water actually delivered in the field is known as__________________?
comments icon0

A. water conveyance efficiency

B. water use efficiency

C. water application efficiency

D. none of the above

78. The best unit duration of storm for a unit hydrograph is________________?
comments icon0

A. equal to basin lag

B. 1 hour

C. one-fourth of basin lag

D. one-half of basin lag

79. The rainfall on five successive days were measured as 100 mm, 80 mm, 60 mm, 40 mm and 20 mm respectively. If the infiltration index or the storm loss rate for the catchment area is earlier estimated as 50 mm/day, the total surface run off will be________________?
comments icon0

A. 50 mm

B. 90 mm

C. 60 mm

D. 140 mm

80. The drainage water intercepting the canal can be disposed of by passing the canal below the drainage in___________________?
comments icon0

A. aqueduct and super passage

B. level crossing

C. super passage and canal syphon

D. aqueduct and syphon aqueduct

81. The maximum rainfall depth of 300 mm in 24 hours has a return period of 100 years. The probability of 24 hours rainfall equal to or greater than 300 mm occurring at least once in 10 years is given by_____________?
comments icon0

A. (0.9)00

B. 1 (0.99)10

C. (0.99)10

D. l-(0.9)100

82. The main cause of meandering is________________?
comments icon0

A. degradation

B. the extra turbulence generated by the excess of river sediment during floods

C. presence of an excessive bed slope in the river

D. none of the above

83. Which of the following is a flexible outlet ?
comments icon0
A. Kennedys gauge outlet

B. submerged pipe outlet

C. none of the above

D. Gibbs outlet

84. The stream which does not have any base flow contribution is called________________?
comments icon0

A. none of the above

B. intermittent stream

C. ephemeral stream

D. perennial stream

85. The forces, which are considered for the analysis of an elementary profile of a gravity dam under empty reservoir condition, are________________?
comments icon0

A. Uplift

B. Water pressure

C. Pressure due to earthquake</strong>

D. correct answer is

E. Self weight

86. Seepage through embankments in an earthen dam is controlled by_______________?
comments icon0

A. provision of downstream berms

B. drainage filters

C. drain trenches

D. relief wells

87. A river training work is generally required when the river is_______________?
comments icon0

A. aggrading type

B. degrading type

C. meandering type

D. both (A) and (B)

88. A current meter is used to measure the__________________?
comments icon0
A. velocity of flow of water

B. depth of flow of water

C. discharge

D. none of the above

89. Generally the weir is aligned at right angles to the direction of the main river current because______________?
comments icon0

A. it is economical

B. all of the above

C. it ensures less length of the weir

D. it gives better discharging capacity

90. Rate of evaporation from a water surface increases if_________________?
comments icon0

A. correct answer is?

B. concentration of soluble solids in water is decreased</strong>

C. difference of vapour pressure between water and air is increased

D. velocity of wind is decreased

91. Which of the following methods is used to estimate flood discharge based on high water marks left over in the past ?
comments icon0
A. slope-area method

B. area-velocity method

C. ultra-sonic method

D. moving boat method

92. Tortuosity of a meandering river is the ratio of__________________?
comments icon0

A. meander belt to meander length

B. curved length along the channel to the direct axial length of the river reach

C. meander length to meander belt

D. direct axial length of the river reach to curved length along the channel

93. Instantaneous unit hydrograph is a hydrograph of________________?
comments icon0

A. correct answer is?

B. unit duration

C. unit rainfall excess

D. infinitely small rainfall excess</strong>

E. infinitely small duration

94. Select the correct statement?
comments icon0
A. A meander increases the river length but a cut off reduces the river length

B. A cutoff increases the river length but a meander reduces the river length

C. Both meander and cutoff increase the river length

D. Both meander and cutoff decrease the river length

95. The maximum permissible eccentricity for no tension at the base of a gravity dam is__________________?
comments icon0
A. B/6

B. B/3

C. B/4

D. B/2

96. To determine the discharge at a section in a stream from its rating curve, the required data are_______________?
comments icon0

A. stage at the section

B. correct answer is?

C. slope of water surface at the section

D. current meter readings at the section </strong>

97. In case of non-availability of space due to topography, the most suitable spillway is________________?
comments icon0

A. ogee spillway

B. chute spillway

C. shaft spillway

D. straight drop spillway

98. Infiltration is the_______________?
comments icon0
A. movement of water through the soil

B. absorption of water by soil surface

C. both (A) and (B)

D. none of the above

99. The net speed under which the turbine reaches its peak efficiency is called_________________?
comments icon0

A. operating speed

B. rated speed

C. gross speed

D. design speed
100. Wetted perimeter of a regime channel for a discharge of 64 cumecs as per Laceys theory will be_________?
comments icon0

A. 76m

B. 19 m

C. 57m

D. 38m