   ## Irrigation MCQ Practice Questions (Civil Engineering) Set 1

##### A hydraulic jump is generally formed when a stream moving with:

Options are :

• A hyper-critical velocity meets a stream moving with a hyper-critical velocity
• A hyper-critical velocity meets a stream moving with a sub-critical velocity
• A hyper-critical velocity meets a stream moving with a critical velocity
• A sub-critical velocity meets a stream moving with a hyper-critical velocity

Answer :A hyper-critical velocity meets a stream moving with a sub-critical velocity

Options are :

• 60░
• 90░
• 30░
• 45░

##### The useful moisture of soil, is equal to its:

Options are :

• Saturation capacity
• Difference between filed capacity and permanent wilting point within the root zone of plants
• Moisture content at permanent wilting point
• Field capacity

Answer :Difference between filed capacity and permanent wilting point within the root zone of plants

##### Canals taken off from ice-fed perennial rivers, are known:

Options are :

• Ridge canals
• Permanent canals
• Ice canals
• Perennial canals
• Inundation canals

##### The Lacey's regime velocity is proportional to:

Options are :

• Q^(3/4) S^(1/3)
• R^(3/4) S^(1/3)
• R^(2/3) S^(1/2)
• R^(1/2) S^(3/4)

##### The velocity of drainage water in the barrels of a syphon-aqueduct, is normally limited to:

Options are :

• 2 to 3 m per second
• 1 to 2 m per second
• 3 to 4 m per second
• 4 to 5 m per second

Answer :2 to 3 m per second

##### If D is the depth of water upstream of the throat above its sill, B is the width of the throat, to achieve critical flow in an open venturi flume, the theoretical maximum flow Q, is:

Options are :

• None of these
• Q = 1.71 BD^(3/2)
• Q = 1/71 BD^(2/3)
• Q = 1.71 BD^(1/2)
• Q = 1.71 BD

##### According to Bligh's creep theory, percolating water flows along:

Options are :

• Straight path under the foundation of the dam
• The outline of the base of the foundation of the dam
• None of these
• Circular path under the foundation of the dam

Answer :The outline of the base of the foundation of the dam

##### A deficit of sediments in flowing water may cause a river:

Options are :

• Meandering type
• Sub-critical type

Options are :

• B
• C
• A
• D

Options are :

• 12.0 cm
• 19.0 cm
• 17.5 cm
• 23.0 cm
• 13.5 cm

##### If H and d are the water depth and drop in the bed level at a Sarda fall, the width B of the trapezoidal crest, is given by:

Options are :

• B = 0.33 ?H + d
• B = 0.22 ?H + d
• B = 0.44 ?H + d
• B = 0.55 ?H + d

Answer :B = 0.55 ?H + d

##### The length and width of a meander and also the width of the river, vary roughly as:

Options are :

• Square root of the discharge
• Cube of the discharge
• Square of the discharge
• Discharge

Answer :Square root of the discharge

Options are :

• 15 cm
• 10 cm
• 25 cm
• 20 cm
• 30 cm

Options are :

• 1.00
• 1.50
• Zero
• 2.00
• 0.50

##### In Montague type fall:

Options are :

• No glacis is provided
• A parabolic glacis is provided
• A straight glacis is provided
• A circular glacis is provided

Answer :A parabolic glacis is provided

##### For a unique design of a channel by Kennedy's theory:

Options are :

• Its breadth must only be known
• All the above
• Its depth must only be known
• Its breadth and depth ratio must only be known

##### Canals constructed for draining off water from water logged areas, are known:

Options are :

• Drains
• Inundation canals
• Contour canals
• Ridge canals
• Valley canals

Options are :

• 12 cm
• 16 cm
• 14 cm
• 8 cm
• 10 cm

##### Pick up the correct statement from the following:

Options are :

• The full supply level of a canal should be above ground level
• In case the ground slope is less than the required bed slope, the silt factor must be reduced by permitting the entry of coarse silt
• According to Lacey, regime conditions require a particular slope for a given discharge and silt factor
• All the above

##### The structure constructed to allow drainage water to flow under pressure through an inverted syphon below a canal, is called:

Options are :

• Aqueduct
• Syphon aqueduct
• Super passage
• Super-aqueduct
• Syphon

##### The state of the soil when plants fail to extract sufficient water for their requirements, is:

Options are :

• None of these
• Permanent wilting point
• Maximum saturated point
• Ultimate utilisation point

##### Useful soil moisture for plant growth, is:

Options are :

• Gravity water
• All the above
• Capillary water
• Chemical water
• Hygroscopic water

##### The width of a meander belt is the transverse distance between:

Options are :

• Apex point of one curve and apex point of the reserve curve
• None of these
• Apex point and the crossing
• Two banks of meandering river

Answer :Apex point of one curve and apex point of the reserve curve

Options are :

• E
• B
• A
• D
• C

##### Regime conditions in a channel may occur if:

Options are :

• Silt grade and silt charge are constant
• All the above
• Discharge is constant
• Channel flows uniformly in incoherent alluvium as that transported in suspension

##### Pick up the correct statement from the following:

Options are :

• Capillary moisture held in the soil pores against gravity by surface tension, is utilised by plants
• Gravity water is harmful to crops
• All the above
• Hygroscopic water remains attached to soil molecules by chemical bond

Answer :Capillary moisture held in the soil pores against gravity by surface tension, is utilised by plants

Options are :

• 19.0 cm
• 12.0 cm
• 17.5 cm
• 13.5 cm
• 23.0 cm

##### According to Khosla, the exist gradient of surface flow:

Options are :

• Depends upon the b/d ratio
• None of these
• Is independent of the b/d ratio
• Is independent of the depths of d/s cut off walls

Answer :Depends upon the b/d ratio

Options are :

• C
• A
• D
• B