The Lacey's regime velocity is proportional to

loss of head follows the sine curve.

The level of the fioor of a syphon aqueduct can be obtained

by subtracting the depth of the culvert from the canal bed level

by subtracting the thickness of culvert plus the depth of the culvert from the canal bed level

According to Khosla, the exist gradient of surface flow

is independent of the b/d ratio

is independent of the depths of d/s cut off walls

Bligh's theory of seepage assumes

more weightage to horizontal creep than vertical creep

equal weightage to the horizontal and vertical creep

more weightage to horizontal creep than vertical creep

less weightage to horizontal creep than vertical creep

loss of head follows the sine curve.

A current meter measures the velocity of flow, if it is held

at any point within the cross-section

If water table is comparatively high, the irrigation canal becomes useless, due to

water logging of the cultivated areas

For the design of major hydraulic structures on the canals, the method generally preferred to, is based on

Khosla's method of independent variables.

canal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal trough.

drainage passes over the canal and F.S.L. of the canal is below the bottom of the drainage trough

drainage passes over the canal and F.S.L. of the canal is above the bottom of the drainage trough

canal passes over the drainage and H.F.L. of the drainage is above the bottom of the canal trough

canal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal trough.

Side slopes generally kept for canals in loam soil, are :

1 : 1 in cutting and : 1 in filling

: 1 in cutting and 2 : 1 in filling

For a given discharge in a channel, Blench curves give the relationship between the loss of head (HL) and

critical depth of water down-stream

Water-shed line is abondened for aligning an irrigation canal if

canal has to take off from a river

towns and villages are located on the water shed line

The length of a meander is the distance along the river between the tangent point of one curve to the tangent point of

reverse curve plus the width of the river

According to G.W. Pickles the effect of confining the flood water of a river between levee, is to increase

water surface elevation during floods

189 + Mcqs in Irrigation in Civil Engineering Page 4 McqOptions

151.	The Lacey's regime velocity is proportional to
A.	loss of head follows the sine curve.
B.	R1/2 S3/4
C.	Q3/4 S1/3
D.	R3/4 S1/3
Answer» D. R3/4 S1/3

Discussion

152.	If the irrigation efficiency is 80%, conveyance losses are 20% and the actual depth of watering is 16 cm, the depth of water required at the canal outlet, is
A.	10 cm
B.	15 cm
C.	20 cm
D.	25 cm
Answer» E.

Discussion

153.	While deciding the alignment of a proposed canal taking off from a river at B, three alignments of approximately equal lengths are available. These cross a drainages at C1, C2 and C3 where drainage bed levels C1 > C2 > C3, you will provide at site C3
A.	an aqueduct
B.	a syphon aqueduct
C.	a super passage
D.	a syphon.
Answer» B. a syphon aqueduct

Discussion

154.	In a concrete canal the approximate permissible velocity of water should not exceed
A.	0.5 m/sec
B.	1 m/sec
C.	1.5 m/sec
D.	2 m/sec
Answer» E.

Discussion

155.	The field capacity of a soil is 25%, its permanent wilting point is 15% and specific dry unity weight is 1.5. If the depth of root zone of a crop, is 80 cm, the storage capacity of the soil, is
A.	8 cm
B.	10 cm
C.	12 cm
D.	14 cm
Answer» D. 14 cm

Discussion

156.	The level of the fioor of a syphon aqueduct can be obtained
A.	by subtracting the depth of the culvert from the canal bed level
B.	by subtracting the thickness of culvert plus the depth of the culvert from the canal bed level
C.	both (a) and (b)
D.	none of these.
Answer» C. both (a) and (b)

Discussion

157.	The ratio of the discharge over a trapezoidal crest to a rectangular crest of Sarda falls of identical parameters, is
A.	1.084
B.	1.074
C.	1.064
D.	1.054
Answer» B. 1.074

Discussion

158.	According to Khosla, the exist gradient of surface flow
A.	depends upon the b/d ratio
B.	is independent of the b/d ratio
C.	is independent of the depths of d/s cut off walls
D.	none of these.
Answer» B. is independent of the b/d ratio

Discussion

159.	If d1 is the depth of cutting, d2 is the height of the bank from bed level r2 : 1 and r1 : 1 are the slopes in filling and cutting respectively, the horizontal distance n between the bed and bank, is
A.	x = r1 d1
B.	x = r2 d2
C.	x = d1 / r1
D.	x = d2 / r2
Answer» C. x = d1 / r1

Discussion

160.	Solution of Laplacian equation in three dimensions of water in a syphon, is done by
A.	analytical method
B.	Khosla's method
C.	method of relaxation
D.	Unwin's method.
Answer» D. Unwin's method.

Discussion

161.	Bligh's theory of seepage assumes
A.	equal weightage to the horizontal and vertical creep
B.	more weightage to horizontal creep than vertical creep
C.	less weightage to horizontal creep than vertical creep
D.	loss of head follows the sine curve.
Answer» B. more weightage to horizontal creep than vertical creep

Discussion

162.	Garnett's diagrams are used for graphical solution of design equations of a canal by
A.	Lacey's theory
B.	Kennedy's theory
C.	Gibb's theory
D.	Lindlay theory.
Answer» C. Gibb's theory

Discussion

163.	For standing crops in undulating sandy fields, the best method of irrigation, is
A.	sprinkler irrigation
B.	free flooding
C.	check method
D.	furrow method
Answer» B. free flooding

Discussion

164.	A current meter measures the velocity of flow, if it is held
A.	on the surface of water
B.	at the bottom of channel
C.	at any point within the cross-section
D.	none of these.
Answer» D. none of these.

Discussion

165.	An outlet which maintains a constant discharge irrespective of fluctuation in the water levels of the supplying channel or water course, is known as
A.	non-modular outlet
B.	semi-modular outlet
C.	flexible modular outlet
D.	right modular outlet.
Answer» E.

Discussion

166.	According to Lacey, depth of scour in a river depends upon the straightness of the reach. If D is the depth of scour in regime flow in a right angled bend, it is
A.	1.25 D
B.	1.50 D
C.	1.75 D
D.	2.00 D
Answer» E.

Discussion

167.	The structure constructed to allow drainage water to flow under pressure through an inverted syphon below a canal, is called
A.	syphon
B.	super passage
C.	aqueduct
D.	super-aqueduct
Answer» E.

Discussion

168.	The down stream expansion head of a guide bank is extended to subtend an angle at the centre, equal to
A.	30¬∞
B.	45¬∞
C.	60¬∞
D.	90¬∞
Answer» C. 60¬∞

Discussion

169.	The width of a dowla is generally kept between 30 to 60 cm and its height above the road level should invariably be more than
A.	10 cm
B.	20 cm
C.	30 cm
D.	40 cm
Answer» D. 40 cm

Discussion

170.	The state of the soil when plants fail to extract sufficient water for their requirements, is
A.	maximum saturated point
B.	permanent wilting point
C.	ultimate utilisation point
D.	none of these.
Answer» E.

Discussion

171.	If water table is comparatively high, the irrigation canal becomes useless, due to
A.	large amount of seepage
B.	water logging of the cultivated areas
C.	uncertain water demand
D.	spread of malaria
Answer» E.

Discussion

172.	For the design of major hydraulic structures on the canals, the method generally preferred to, is based on
A.	Bligh's theory
B.	Electrical analogy method
C.	The relaxation method
D.	Khosla's method of independent variables.
Answer» E.

Discussion

173.	In a syphon aqueduct
A.	drainage passes over the canal and F.S.L. of the canal is below the bottom of the drainage trough
B.	drainage passes over the canal and F.S.L. of the canal is above the bottom of the drainage trough
C.	canal passes over the drainage and H.F.L. of the drainage is above the bottom of the canal trough
D.	canal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal trough.
Answer» D. canal passes over the drainage and H.F.L. of the drainage is below the bottom of the canal trough.

Discussion

174.	For smooth entry of water in a canal, the angle between head regulator and water is generally kept
A.	80¬∞
B.	90¬∞
C.	110¬∞
D.	120¬∞
Answer» D. 120¬∞

Discussion

175.	Side slopes generally kept for canals in loam soil, are :
A.	1 : 1 in cutting and : 1 in filling
B.	: 1 in cutting and 2 : 1 in filling
C.	Neither (a) nor (b)
D.	Both (a) and (b)
Answer» E.

Discussion

176.	For a given discharge in a channel, Blench curves give the relationship between the loss of head (HL) and
A.	specific energy up-stream
B.	specific energy down-stream
C.	critical depth of water down-stream
D.	depth of water down-stream
Answer» C. critical depth of water down-stream

Discussion

177.	The saturation line is the line up to which banks get saturated after the canal runs for some time. The saturation gradient in ordinary loam soil, is generally
A.	0.084027777777778
B.	0.12569444444444
C.	0.16736111111111
D.	0.20902777777778
Answer» D. 0.20902777777778

Discussion

178.	Water-shed line is abondened for aligning an irrigation canal if
A.	water shed forms a sharp loop
B.	canal has to take off from a river
C.	towns and villages are located on the water shed line
D.	all the above.
Answer» E.

Discussion

179.	The depth of the crest of a scouring sluice below the crest of a head regulator, is generally kept
A.	0.20 m
B.	1.20 m
C.	2.20 m
D.	3.20 m
Answer» C. 2.20 m

Discussion

180.	For the conditions enumerated to provide a crossing at C1 You will probably provide
A.	an aqueduct
B.	a super-passage
C.	a syphon aqueduct
D.	none of these.
Answer» C. a syphon aqueduct

Discussion

181.	For loss of head in a canal inverted syphon barrel, the factor in the Unwin formula is a coefficient for loss of head due to
A.	friction
B.	exit
C.	entry
D.	gradient
Answer» D. gradient

Discussion

182.	When a canal flowing under pressure is carried below a natural drainage such that its F.S.L. does not touch the underside of the supporting structure, the structure so provided, is called
A.	syphon
B.	aqueduct
C.	super passage
D.	syphon-aqueduct.
Answer» D. syphon-aqueduct.

Discussion

183.	When a canal and a drainage approach each other at the same level, the structure so provided, is
A.	an aqueduct
B.	a syphon
C.	a level crossing
D.	inlet and outlet.
Answer» D. inlet and outlet.

Discussion

184.	For the stability of a structure against seepage pressure according to Khosla's creep theory, the critical gradient is
A.	zero
B.	0.25
C.	0.5
D.	0.75
Answer» E.

Discussion

185.	The discharge over a trapezoidal crest of a Sarda fall with free over fall conditions, is
A.	0.45 2g . LH3/2 (H/B)1/3
B.	0.45 2g . LH2/3 (H/B)2/3
C.	0.45 2g . LH3/2 (H/B)1/6
D.	0.45 2g . LH1/6 (H/B)3/2
Answer» D. 0.45 2g . LH1/6 (H/B)3/2

Discussion

186.	The length of a meander is the distance along the river between the tangent point of one curve to the tangent point of
A.	reverse curve
B.	next curve of the same order
C.	reverse curve plus the width of the river
D.	none of these.
Answer» C. reverse curve plus the width of the river

Discussion

187.	According to G.W. Pickles the effect of confining the flood water of a river between levee, is to increase
A.	rate of flood wave
B.	water surface elevation during floods
C.	maximum discharge
D.	velocity and scouring action
Answer» E.

Discussion

188.	If the straight sides of a triangular section of a lined canal with circular bottom of radius D, make an angle Œ∏ with horizontal, the hydraulic mean depth is
A.	D
B.	D/2
C.	D/3
D.	D/4
Answer» C. D/3

Discussion

189.	The difference in level between the top of a bank and supply level in a canal, is called
A.	berm
B.	free board
C.	height of bank
D.	none of these.
Answer» C. height of bank

Discussion

Explore topic-wise MCQs in Civil Engineering.

The Lacey's regime velocity is proportional to

If the irrigation efficiency is 80%, conveyance losses are 20% and the actual depth of watering is 16 cm, the depth of water required at the canal outlet, is

While deciding the alignment of a proposed canal taking off from a river at B, three alignments of approximately equal lengths are available. These cross a drainages at C1, C2 and C3 where drainage bed levels C1 > C2 > C3, you will provide at site C3

In a concrete canal the approximate permissible velocity of water should not exceed

The field capacity of a soil is 25%, its permanent wilting point is 15% and specific dry unity weight is 1.5. If the depth of root zone of a crop, is 80 cm, the storage capacity of the soil, is

The level of the fioor of a syphon aqueduct can be obtained

The ratio of the discharge over a trapezoidal crest to a rectangular crest of Sarda falls of identical parameters, is

According to Khosla, the exist gradient of surface flow

If d1 is the depth of cutting, d2 is the height of the bank from bed level r2 : 1 and r1 : 1 are the slopes in filling and cutting respectively, the horizontal distance n between the bed and bank, is

Solution of Laplacian equation in three dimensions of water in a syphon, is done by

Bligh's theory of seepage assumes

Garnett's diagrams are used for graphical solution of design equations of a canal by

For standing crops in undulating sandy fields, the best method of irrigation, is

A current meter measures the velocity of flow, if it is held

An outlet which maintains a constant discharge irrespective of fluctuation in the water levels of the supplying channel or water course, is known as

According to Lacey, depth of scour in a river depends upon the straightness of the reach. If D is the depth of scour in regime flow in a right angled bend, it is

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

The down stream expansion head of a guide bank is extended to subtend an angle at the centre, equal to

The width of a dowla is generally kept between 30 to 60 cm and its height above the road level should invariably be more than

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

If water table is comparatively high, the irrigation canal becomes useless, due to

For the design of major hydraulic structures on the canals, the method generally preferred to, is based on

In a syphon aqueduct

For smooth entry of water in a canal, the angle between head regulator and water is generally kept

Side slopes generally kept for canals in loam soil, are :

For a given discharge in a channel, Blench curves give the relationship between the loss of head (HL) and

The saturation line is the line up to which banks get saturated after the canal runs for some time. The saturation gradient in ordinary loam soil, is generally

Water-shed line is abondened for aligning an irrigation canal if

The depth of the crest of a scouring sluice below the crest of a head regulator, is generally kept

For the conditions enumerated to provide a crossing at C1 You will probably provide

For loss of head in a canal inverted syphon barrel, the factor in the Unwin formula is a coefficient for loss of head due to

When a canal flowing under pressure is carried below a natural drainage such that its F.S.L. does not touch the underside of the supporting structure, the structure so provided, is called

When a canal and a drainage approach each other at the same level, the structure so provided, is

For the stability of a structure against seepage pressure according to Khosla's creep theory, the critical gradient is

The discharge over a trapezoidal crest of a Sarda fall with free over fall conditions, is

The length of a meander is the distance along the river between the tangent point of one curve to the tangent point of

According to G.W. Pickles the effect of confining the flood water of a river between levee, is to increase

If the straight sides of a triangular section of a lined canal with circular bottom of radius D, make an angle Œ∏ with horizontal, the hydraulic mean depth is

The difference in level between the top of a bank and supply level in a canal, is called