Quiznetik

Irrigation Engineering | Set 1

1. Which of the following methods of applying water may be used on rolling land ?

Correct : A. boarder flooding

2. The value of Sodium Absorption Ratio for high sodium water lies between

Correct : C. 18 to 26

3. Optimum depth of kor watering for rice is

Correct : C. 190 mm

4. Irrigation water having the concentration of Na++ , Ca++ and Mg++ as 20, 3 and 1 Milli equivalent per litre respectively will be classified as

Correct : B. medium sodium water

5. The duty is largest

Correct : B. on the field

6. The "outlet discharge factor" is the duty at the head of

Correct : C. watercourse

7. The kor depth for rice is 190 mm and kor period is 14 days. The outlet factor for this will be

Correct : A. 637 hectares/m3/sec

8. For supplying water to rabi crop, kharif crop and sugarcane, the channel is designed for a capacity equal to the greater of the water requirement of

Correct : C. rabi and sugarcane or kharif and sugarcane

9. 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

Correct : B. water application efficiency

10. The water utilizable by plants is available in soils mainly in the form of

Correct : B. capillary water

11. The amount of irrigation water required to meet the evapotranspiration needs of the crop during its full growth is called

Correct : C. consumptive irrigation requirement

12. With the increase in the quantity of water supplied, the yield of most crops

Correct : D. increases upto a certain limit and then decreases

13. Hydrograph is the graphical representation of

Correct : A. runoff and time

14. Infiltration rate is always

Correct : C. equal to or less than the infiltration capacity

15. The depth of water required to bring the soil moisture content of a given soil upto its field capacity is called

Correct : C. soil moisture deficiency

16. Infiltration capacity

Correct : D. changes with both time and location

17. Infiltration is the

Correct : A. movement of water through the soil

18. If the intensity of rainfall is more than the infiltration capacity of soil, then the infiltration rate will be

Correct : B. equal to infiltration capacity

19. Cyclonic precipitation is caused by lifting of an air mass due to

Correct : A. pressure difference

20. Which of the following is a non-recording raingauge ?

Correct : B. Simon's raingauge

21. A raingauge should preferably be fixed

Correct : C. in an open space

22. Which of the following types of rain gauges is used for measuring rain in remote hilly inaccessible areas ?

Correct : A. tipping bucket type

23. Rate of evaporation from a water surface increases if i) difference of vapour pressure between water and air is increased ii) velocity of wind is decreased iii) concentration of soluble solids in water is decreased The correct answer is

Correct : B. (i) and (iii)

24. A 70% index of wetness means

Correct : B. rain deficiency of 30%

25. Under the same conditions, which of the following shapes of water surface will give the highest rate of evaporation ?

Correct : B. convex water surface

26. 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 :

Correct : A. Both A and R are true and R is the correct explanation of A

27. When surface of transpiration is submerged under water, then potential evapotranspiration is

Correct : A. much more than evapotranspiration

28. Unit of runoff in M.K.S. system is

Correct : A. cubic metre/sec

29. The runoff increases with

Correct : A. increase in intensity of rain

30. The area between the isohyets 45 cm and 55 cm is 100 square km and between 55 cm and 65cm is 150 square km. The average depth of annua! precipitation over the above basin of 250 square km will be

Correct : C. 56 cm

31. A current meter is used to measure the

Correct : A. velocity of flow of water

32. If it rains between 2 P.M. and 3 P.M. and the entire basin area just starts contributing water at 3 P.M. to the outlet, then time of concentration will be

Correct : D. 60 minutes

33. 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

Correct : C. 90 mm

34. 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

Correct : A. 70mm

35. The best unit duration of storm for a unit hydrograph is

Correct : B. one-fourth of basin lag

36. The unit hydrograph due to a storm may be obtained by dividing the ordinates of the direct runoff hydrograph by

Correct : A. direct runoff volume

37. The unit hydrograph of a specified duration can be used to evaluate the hydrograph of storms of

Correct : D. any duration

38. S-hydrograph is used to obtain unit hydrograph of

Correct : C. both (a) and (b)

39. The relation between probability (P) and recurrence interval (T) is given by

Correct : A. PT = 1

40. Dimensions of coefficient of transmissibility are

Correct : C. M° L2 T1

41. 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

Correct : A. T = kd

42. An artesian aquifer is the one where

Correct : B. water is under pressure between two impervious strata

43. A deep well

Correct : B. has more discharge than a shallow well

44. A multipurpose reservoir is the one which is

Correct : B. planned and constructed to serve various purposes

45. The useful storage is the volume of water stored in the reservoir between

Correct : B. minimum pool level and normal pool level

46. The water stored in the reservoir below the minimum pool level is called

Correct : B. dead storage

47. For a flood control reservoir, the effective storage is equal to

Correct : D. useful storage + surcharge storage -valley storage

48. Trap efficiency of a reservoir is a function of

Correct : A. capacity/inflow ratio

49. 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

Correct : A. 50 years

50. The forces, which are considered for the analysis of an elementary profile of a gravity dam under empty reservoir condition, are i) Water pressure ii) Self weight iii) Uplift iv) Pressure due to earthquake The correct answer is

Correct : A. Only (ii)

51. When the upstream face of a gravity dam is vertical, then the intensity of water pressure at the water surface and at the base respectively will be (where w is unit weight of water and H is the depth of water.)

Correct : D. OandwII

52. The uplift pressure on a dam can be controlled by i) constructing cutoff under upstream face ii) constructing drainage channels bet-ween the dam and its foundation iii) by pressure grouting in foundation The corret answer is

Correct : D. (i), (ii) and (iii)

53. The uplift pressure on the face of a drainage gallery in a dam is taken as

Correct : C. two-third of hydrostatic pressure at toe plus one-third of hydrostatic pressure at heel

54. Horizontal acceleration due to earthquake results in

Correct : C. both (a) and (b)

55. Hydrodynamic pressure due to earthquake acts at a height of

Correct : C. 4H/371 above the base

56. The major resisting force in a gravity dam is

Correct : C. self-weight of dam

57. When the reservoir is full, the maximum compressive force in a gravity dam is produced

Correct : A. at the toe

58. The maximum permissible eccentricity for no tension at the base of a gravity dam is

Correct : D. B/6

59. Presence of tail water in a gravity dam i) increases the principal stress ii) decreases the principal stress iii) increases the shear stress iv) decreases the shear stress The correct answer is

Correct : D. (ii) and (iv)

60. For wave action in dams, the maximum height of freeboard is generally taken to be equal to (where hw is height of wave.)

Correct : D. 1.50 hw

61. As compared to gravity dams, earthen dams

Correct : D. require less skilled labour

62. The most suitable material for the central impervious core of a zoned embankment type dam is

Correct : D. clay mixed with fine sand

63. Seepage through embankments in an earthen dam is controlled by

Correct : C. drain trenches

64. Seepage through foundation in an earthen dam is controlled by providing

Correct : C. impervious cut off

65. The flow of water after spilling over the weir crest in chute spillway and side channel spillway respectively are

Correct : A. at right angle and parallel to weir crest

66. The discharge passing over an ogee spillway is given by (where, L is effective length of spillway crest and H is the total head over the spillway crest including velocity head.)

Correct : A. CLH3/2

67. Coefficient of discharge of an ogee spillway

Correct : D. both (a) and (b)

68. Which of the following spillways is least suitable for an earthen dam ?

Correct : A. ogee spillway

69. In case of non-availability of space due to topography, the most suitable spillway is

Correct : B. shaft spillway

70. In a chute spillway, the flow is usually

Correct : D. super critical

71. For the upstream face of an earthen dam, the most adverse condition for stability of slope is

Correct : A. sudden drawdown

72. If there are two canals taking off from each flank of a river, then there will be

Correct : D. two divide walls and two undersluices

73. Generally the weir is aligned at right angles to the direction of the main river current because

Correct : D. all of the above

74. The main function of a divide wall is to

Correct : C. separate the undersluices from weir proper

75. A divide wall is provided

Correct : A. at right angle to the axis of weir

76. As compared to crest of the normal portion of the weir, the crest of the under sluice portion of weir is kept at

Correct : A. lower level

77. Silt excluders are constructed on the

Correct : A. river bed upstream of head regulator

78. According to Khosla's theory, the exit gradient in the absence of a downstream cutoff is

Correct : C. infinity

79. 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

Correct : B. 11 RS

80. The ratio of average values of shear stresses produced on the bed and the banks of a channel due to flowing water is

Correct : C. greater than 1

81. 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

Correct : B. 0.75 TC

82. As per Lacey's theory, the silt factor is

Correct : C. directly proportional to square root of average particle size

83. Wetted perimeter of a regime channel for a discharge of 64 cumecs as per Lacey's theory will be

Correct : B. 38m

84. Which of the following canal structures is used to remove surplus water from an irrigation channel into a natural drain ?

Correct : C. canal escape

85. For a proportional outlet, the flexibility is

Correct : C. 1

86. The sensitivity of a rigid module is

Correct : A. zero

87. Which of the following is a flexible outlet ?

Correct : B. Kennedy's gauge outlet

88. A straight glacis type fall with a baffle platform and a baffle wall is called

Correct : D. inglis fall

89. Which of the following types of falls use parabolic glacis for energy dissipation ?

Correct : C. Montague type fall

90. In a Sarda type fall, rectangular crest is used for discharge upto

Correct : C. 14 cumecs

91. Which of the following can be used as a meter fall ?

Correct : A. vertical drop fall

92. Vertical drop fall is satisfactory for a height upto

Correct : B. 1.5 m

93. Which of the following canal outlets maintains a constant discharge ?

Correct : C. rigid module

94. The ratio of rate of change of the discharge of an outlet to the rate of change of the discharge of distributing channel is called

Correct : B. flexibility

95. The drainage water intercepting the canal can be disposed of by passing the canal below the drainage in

Correct : C. super passage and canal syphon

96. If the R.L's of canal bed level and high flood level of drainage are 212.0 m and 210.0 m respectively, then cross drainage work will be

Correct : C. syphon

97. The aqueduct or superpassage type of works are generally used when

Correct : A. high flood drainage discharge is small

98. An aggrading river is a

Correct : A. silting river

99. Tortuosity of a meandering river is the ratio of

Correct : C. curved length along the channel to the direct axial length of the river reach

100. The meander pattern of a river is developed by

Correct : B. dominant discharge