The energy dissipation at the toe of the spillway is affected basically by the use of hydraulic jump in _______________________

both roller and ski-jump bucket

a sloping apron below the downstream river bed

both roller and ski-jump bucket

The formation of hydraulic jump at the foot of a spillway is one of the common methods of energy dissipation because ______________________

it reduces the kinetic energy by increasing the depth of flow

it destroys more than 90% of total energy by the turbulence produced in the jump

it reduces the kinetic energy by increasing the depth of flow

it reduces the kinetic energy by decreasing the depth of flow

When the tail-water depths in the river downstream of a spillway are quite low such that the tail-water curve at all discharges lies below the post jump depth curve, then the energy dissipation can be affected best by ___________________

either roller or ski-jump bucket

A sloping apron is provided partly above the river bed and partly below the river bed in case of ____________________________

when TWC coincides with the JHC at all discharges

when TWC lies above the JHC at all discharges

when TWC lies below the JHC at all discharges

when TWC lies above the JHC at low discharges and below the JHC at high discharges

If the head of the water over the spillway is less than the design head, then ________________

the pressure on the crest will be zero

the pressure on the crest will be negative causing cavitation

the discharge coefficient of the spillway is increased

the discharge coefficient of the spillway will be reduced

When the crest of an ogee spillway is designed to be in accordance with the lower nappe of a free-falling water jet over a duly ventilated sharp-crested weir then theoretically

The pressure on the spillway crest will always be zero

The pressure on the spillway crest will be zero at design head only

The pressure on the spillway crest will always be zero

The pressure on the spillway crest will always be negative

The pressure on the spillway crest will be always positive

If a flood enters a dam reservoir at F.R.L, the efficiency of its ogee spillway will ______________

reduce with the increasing head

increase with the increasing head

reduce with the increasing head

remain constant with the increasing head

In the functioning of an ogee spillway, the operating head ______________________

frequently exceeds the design head

has no connection with the design head

If the operating head on an ogee spillway is more than the design head then ________________

the pressure on the crest will be positive

the pressure on the crest will be zero

the pressure on the crest will be negative causing cavitation

the pressure on the crest will be positive

the discharge coefficient of the spillway will be reduced

In the vertical Stoney spillway gate, the rollers are placed between the ______________

attached to the gate and groove guides

Morning glory is the _____________________________

a horizontal tunnel constructed in a shaft spillway across the body of a gravity dam to carry surplus reservoir water to the d/s river

special flared inlet of the shaft spillway of a dam of very small height

special flared inlet of the shaft spillway of a large dam project

a horizontal tunnel constructed in a shaft spillway across the body of a gravity dam to carry surplus reservoir water to the d/s river

a horizontal tunnel constructed in a shaft spillway of an earthen dam through its foundation to carry surplus reservoir water to the d/s river

What is the expected solution for the case when the T.W.C is lying above the J.H.C curve at all discharges?

By providing a sloping apron below the river bed

By providing a simple concrete apron of length 5(Y₁ – Y₂)

By providing a sloping apron above the river bed

By providing a sloping apron below the river bed

An air vent is provided at FRL to break the siphoning action at that level in a ___________________

tilted outlet type of siphon spillway

88 + Mcqs in Spillways and Spillway Gates in Irrigation Engineering Page 1 McqOptions

1.	_____________________ are suitable only for low spillways or weirs.
A.	Chute blocks
B.	Sloping aprons
C.	Baffle wall or friction blocks
D.	Roller buckets
Answer» D. Roller buckets

Discussion

2.	In the case of dam spillways, the approaching Froude number usually lies in the range of __________
A.	less than 2.5 m
B.	2.5 – 4.5
C.	4.5 – 9.0
D.	more than 9.0
Answer» D. more than 9.0

Discussion

3.	The energy dissipation at the toe of the spillway is affected basically by the use of hydraulic jump in _______________________
A.	roller bucket
B.	a ski-jump bucket
C.	a sloping apron below the downstream river bed
D.	both roller and ski-jump bucket
Answer» D. both roller and ski-jump bucket

Discussion

4.	The formation of hydraulic jump at the foot of a spillway is one of the common methods of energy dissipation because ______________________
A.	it destroys more than 90% of total energy by the turbulence produced in the jump
B.	it reduces the kinetic energy by increasing the depth of flow
C.	its action is not understood
D.	it reduces the kinetic energy by decreasing the depth of flow
Answer» B. it reduces the kinetic energy by increasing the depth of flow

Discussion

5.	The most ideal condition for energy dissipation in the design of spillways is the one when the tail-water rating curve coincides with the jump rating curve at all discharge.
A.	True
B.	False
C.	May be True or False
D.	Can't say
Answer» B. False

Discussion

6.	For a saddle siphon, the maximum operative head is 4.53 m. The width and height of the throat of the siphon are 5 m and 2.25 m respectively. The coefficient of discharge is 0.90. How many units are required to pass a flood of 350 cumecs? (Assume g = 10 m/s2)
A.	One
B.	Two
C.	Three
D.	Four
Answer» E.

Discussion

7.	Standard USBR stilling basin-II is useful for energy dissipation at the bottom of the overflow structure, if the approaching Froude number is ________________
A.	less than 4.5
B.	more than 4.5
C.	less than 2.5
D.	more than 2.5
Answer» C. less than 2.5

Discussion

8.	When the tail-water depths in the river downstream of a spillway are quite low such that the tail-water curve at all discharges lies below the post jump depth curve, then the energy dissipation can be affected best by ___________________
A.	a roller bucket
B.	a ski-jump bucket
C.	either roller or ski-jump bucket
D.	a sloping apron
Answer» C. either roller or ski-jump bucket

Discussion

9.	The allowable maximum negative head on an average is equal to __________
A.	2.5 m or so
B.	5 m or so
C.	7.5 m or so
D.	10 m or so
Answer» D. 10 m or so

Discussion

10.	In a fixed roller of a spillway gate, the rollers are attached to the __________________
A.	gate
B.	groove gate
C.	either gate or groove gate
D.	guide grooves
Answer» B. groove gate

Discussion

11.	A sloping apron is provided partly above the river bed and partly below the river bed in case of ____________________________
A.	when TWC coincides with the JHC at all discharges
B.	when TWC lies above the JHC at all discharges
C.	when TWC lies below the JHC at all discharges
D.	when TWC lies above the JHC at low discharges and below the JHC at high discharges
Answer» E.

Discussion

12.	A very steady and stable hydraulic jump is usually formed in the flows involving the approaching Froude number in the range of _____________________
A.	less than 2.5
B.	2.5 to 4.5
C.	4.5 to 9.0
D.	more than 9.0
Answer» D. more than 9.0

Discussion

13.	When the TWC lies below the JHC at all discharges, the problem can be solved by which of the following provisions?i. Constructing a sloping apron above the river bedii. Provision of roller bucket type of energy dissipatoriii. Provision of a ski-jump bucketiv. A sloping apron below the river bedv. Construction of a subsidiary damvi. A sloping apron partly above and partly below the river bed
A.	i, iii and v
B.	i, ii and vi
C.	iii, iv and v
D.	i, iii, iv and v
Answer» D. i, iii, iv and v

Discussion

14.	The only spillway among the following through which the discharge is almost at its capacity rate even from the start of its functioning is ________________
A.	chute spillway
B.	side-channel spillway
C.	ogee spillway
D.	siphon spillway
Answer» E.

Discussion

15.	Which of the following spillway is least suitable to earthen dams?
A.	Ogee spillway
B.	Chute spillway
C.	Side-channel spillways
D.	Shaft spillway
Answer» B. Chute spillway

Discussion

16.	Which of the following spillway is an improvement over free overflow spillway?
A.	Straight drop spillway
B.	Open channel spillway
C.	Overflow spillway
D.	Siphon spillway
Answer» D. Siphon spillway

Discussion

17.	When the gated sluices are provided through the body of the dam spillway then the ogee spillway structure shall normally be of Corbel type.
A.	True
B.	False
C.	May be True or False
D.	Can't say
Answer» C. May be True or False

Discussion

18.	What is the value of the pier abutment coefficient for pointed nose piers?
A.	0.1
B.	0.02
C.	0.01
D.	0.0
Answer» E.

Discussion

19.	A ski-jump bucket is also known as _____________________
A.	flip bucket
B.	solid roller bucket
C.	slotted roller bucket
D.	flexible bucket
Answer» B. solid roller bucket

Discussion

20.	If the upstream face of the spillway is kept vertical, the crest shape should also confirm to the lower nappe of an inclined sharp-crested weir.
A.	True
B.	False
C.	May be True or False
D.	Can't say
Answer» C. May be True or False

Discussion

21.	The discharge passing over an ogee spillway per unit length of its apex line is proportional ___________________
A.	H
B.	H²
C.	H^1/2
D.	H^3/2
Answer» E.

Discussion

22.	When the Froude number is in the range of 2.5 to 4.5, the jump is ____________________
A.	weak and energy loss is low
B.	troublesome and oscillating
C.	steady jump
D.	strong jump
Answer» C. steady jump

Discussion

23.	According to US Army Corps, the u/s profile of ogee spillway extends up to _______________
A.	x = 1.27 Hd
B.	x = -1.27 Hd
C.	x = 0.431 Hd
D.	x = -0.431 Hd
Answer» C. x = 0.431 Hd

Discussion

24.	If the head of the water over the spillway is less than the design head, then ________________
A.	the pressure on the crest will be zero
B.	the pressure on the crest will be negative causing cavitation
C.	the discharge coefficient of the spillway is increased
D.	the discharge coefficient of the spillway will be reduced
Answer» E.

Discussion

25.	Which of the following spillway is designed in India by Ganesh Iyer?
A.	Saddle siphon spillway
B.	Saddle spillway
C.	Glory hole spillway
D.	Volute Siphon spillway
Answer» E.

Discussion

26.	The spillway which can be called as an overflow spillway is essentially ___________________
A.	an ogee spillway
B.	a shaft spillway
C.	a chute spillway
D.	a syphon spillway
Answer» B. a shaft spillway

Discussion

27.	Standard stilling basin is provided at the toe of a dam spillway for energy dissipation is usually provided with auxiliary devices like chute blocks and dentated sills for the basic purpose of reducing the length of the stilling basin from about ________________
A.	6 y₂ to 4 y₂
B.	4 y₂ to 2 y₂
C.	6 y₂ to 2 y₂
D.	3 y₂ to y₂
Answer» B. 4 y₂ to 2 y₂

Discussion

28.	________________ are used only for very minor works.
A.	Dropping gates
B.	Stop logs and needles
C.	Rectangular gates
D.	Drum gates
Answer» C. Rectangular gates

Discussion

29.	Which of the following gate is not suitable for smaller spillways?
A.	Drum gates
B.	Radial gates
C.	Needles and stop logs
D.	Fixed roller gates
Answer» B. Radial gates

Discussion

30.	The percentage of energy dissipation in a hydraulic jump increases with the increase in the Froude number.
A.	True
B.	False
C.	May be True or False
D.	Can't say
Answer» B. False

Discussion

31.	When the crest of an ogee spillway is designed to be in accordance with the lower nappe of a free-falling water jet over a duly ventilated sharp-crested weir then theoretically
A.	The pressure on the spillway crest will be zero at design head only
B.	The pressure on the spillway crest will always be zero
C.	The pressure on the spillway crest will always be negative
D.	The pressure on the spillway crest will be always positive
Answer» B. The pressure on the spillway crest will always be zero

Discussion

32.	Which of the following stilling basin help in stabilizing the flow and improve the jump performance?
A.	dentated sills
B.	chute blocks
C.	baffle piers
D.	friction blocks
Answer» C. baffle piers

Discussion

33.	Which of the following helps in dissipating the residual energy and to reduce the length of the jump or the basin?
A.	Dentated sills
B.	Chute blocks
C.	Roller bucket
D.	Baffle piers
Answer» B. Chute blocks

Discussion

34.	A siphon spillway is sufficiently independent of the water surface elevation of the reservoir.
A.	True
B.	False
C.	May be True or False
D.	Can't say
Answer» B. False

Discussion

35.	Which of the following stilling basin is applicable to only rectangular cross-sections?
A.	U.S.B.R stilling basin-II
B.	U.S.B.R stilling basin-IV
C.	U.S.B.R stilling basin-I
D.	U.S.B.R stilling basin-III
Answer» C. U.S.B.R stilling basin-I

Discussion

36.	If a flood enters a dam reservoir at F.R.L, the efficiency of its ogee spillway will ______________
A.	increase with the increasing head
B.	reduce with the increasing head
C.	remain constant with the increasing head
D.	vary with the increasing head
Answer» B. reduce with the increasing head

Discussion

37.	The device which does not help in energy dissipation at the bottom of a hydraulic structure over which water spills is ________________
A.	chute block
B.	dentated sill
C.	morning glory
D.	baffle piers
Answer» D. baffle piers

Discussion

38.	In the functioning of an ogee spillway, the operating head ______________________
A.	frequently exceeds the design head
B.	rarely exceeds the design head
C.	never exceeds the design head
D.	has no connection with the design head
Answer» C. never exceeds the design head

Discussion

39.	The structure which is not used in a shaft spillway is ________________
A.	tunnel
B.	bridge
C.	radial gates
D.	radial piers
Answer» D. radial piers

Discussion

40.	If the operating head on an ogee spillway is more than the design head then ________________
A.	the pressure on the crest will be zero
B.	the pressure on the crest will be negative causing cavitation
C.	the pressure on the crest will be positive
D.	the discharge coefficient of the spillway will be reduced
Answer» C. the pressure on the crest will be positive

Discussion

41.	Which of the following gate works on the principle of counterweights against the water pressure?
A.	Dropping shutters
B.	Stop logs and needles
C.	Stoney roller gate
D.	Drum gates
Answer» B. Stop logs and needles

Discussion

42.	The W.E.S downstream profile of an ogee spillway can be represented by an equation:Xⁿ = K Hdⁿ⁻¹. YWhere x and y are the coordinates of the points on the crest profile and K and n for a vertical upstream spillway would respectively be___________________
A.	2.0 and 1.85
B.	0.5 and 1.85
C.	2.0 and 0.85
D.	0.5 and 0.85
Answer» B. 0.5 and 1.85

Discussion

43.	In the vertical Stoney spillway gate, the rollers are placed between the ______________
A.	gate and u/s groove guide
B.	gate and the d/s groove guide
C.	u/s and d/s groove guide
D.	attached to the gate and groove guides
Answer» C. u/s and d/s groove guide

Discussion

44.	Morning glory is the _____________________________
A.	special flared inlet of the shaft spillway of a dam of very small height
B.	special flared inlet of the shaft spillway of a large dam project
C.	a horizontal tunnel constructed in a shaft spillway across the body of a gravity dam to carry surplus reservoir water to the d/s river
D.	a horizontal tunnel constructed in a shaft spillway of an earthen dam through its foundation to carry surplus reservoir water to the d/s river
Answer» C. a horizontal tunnel constructed in a shaft spillway across the body of a gravity dam to carry surplus reservoir water to the d/s river

Discussion

45.	The spillway gate which when lowered cannot be seen from a distance is of the type ______________________
A.	Sliding gate
B.	Roller gate
C.	Tainter gate
D.	USBR drum gate
Answer» E.

Discussion

46.	An ogee spillway of a concrete gravity dam having FRL of 328 m and MWL of 340 m is provided with vertical gates between piers erected on the spillway. The effective length of the spillway is 60 m. The discharge through the spillway when gates are opened up to the actual reservoir level of 331.0 m will be_____________
A.	850 cumecs
B.	1700 cumecs
C.	2800 cumecs
D.	1000 cumecs
Answer» C. 2800 cumecs

Discussion

47.	What is the expected solution for the case when the T.W.C is lying above the J.H.C curve at all discharges?
A.	By providing a simple concrete apron of length 5(Y₁ – Y₂)
B.	By providing a sloping apron above the river bed
C.	By providing a sloping apron below the river bed
D.	Provision of a ski-jump bucket
Answer» C. By providing a sloping apron below the river bed

Discussion

48.	An air vent is provided at FRL to break the siphoning action at that level in a ___________________
A.	hooded type of siphon spillway
B.	tilted outlet type of siphon spillway
C.	saddle siphon spillway
D.	volute siphon spillway
Answer» D. volute siphon spillway

Discussion

49.	A troublesome and oscillating hydraulic jump is normally met in cases of _____________
A.	weirs and barrages
B.	overflow spillways of dams
C.	weirs
D.	large spillways
Answer» B. overflow spillways of dams

Discussion

50.	The spillway which can be adopted with ease on gravity as well as earthen dams is _________________
A.	ogee spillway
B.	chute spillway
C.	both ogee and chute spillway
D.	straight drop spillway
Answer» C. both ogee and chute spillway

Discussion

Explore topic-wise MCQs in Irrigation Engineering.

_____________________ are suitable only for low spillways or weirs.

In the case of dam spillways, the approaching Froude number usually lies in the range of __________

The energy dissipation at the toe of the spillway is affected basically by the use of hydraulic jump in _______________________

The formation of hydraulic jump at the foot of a spillway is one of the common methods of energy dissipation because ______________________

The most ideal condition for energy dissipation in the design of spillways is the one when the tail-water rating curve coincides with the jump rating curve at all discharge.

For a saddle siphon, the maximum operative head is 4.53 m. The width and height of the throat of the siphon are 5 m and 2.25 m respectively. The coefficient of discharge is 0.90. How many units are required to pass a flood of 350 cumecs? (Assume g = 10 m/s2)

Standard USBR stilling basin-II is useful for energy dissipation at the bottom of the overflow structure, if the approaching Froude number is ________________

When the tail-water depths in the river downstream of a spillway are quite low such that the tail-water curve at all discharges lies below the post jump depth curve, then the energy dissipation can be affected best by ___________________

The allowable maximum negative head on an average is equal to __________

In a fixed roller of a spillway gate, the rollers are attached to the __________________

A sloping apron is provided partly above the river bed and partly below the river bed in case of ____________________________

A very steady and stable hydraulic jump is usually formed in the flows involving the approaching Froude number in the range of _____________________

The only spillway among the following through which the discharge is almost at its capacity rate even from the start of its functioning is ________________

Which of the following spillway is least suitable to earthen dams?

Which of the following spillway is an improvement over free overflow spillway?

When the gated sluices are provided through the body of the dam spillway then the ogee spillway structure shall normally be of Corbel type.

What is the value of the pier abutment coefficient for pointed nose piers?

A ski-jump bucket is also known as _____________________

If the upstream face of the spillway is kept vertical, the crest shape should also confirm to the lower nappe of an inclined sharp-crested weir.

The discharge passing over an ogee spillway per unit length of its apex line is proportional ___________________

When the Froude number is in the range of 2.5 to 4.5, the jump is ____________________

According to US Army Corps, the u/s profile of ogee spillway extends up to _______________

If the head of the water over the spillway is less than the design head, then ________________

Which of the following spillway is designed in India by Ganesh Iyer?

The spillway which can be called as an overflow spillway is essentially ___________________

Standard stilling basin is provided at the toe of a dam spillway for energy dissipation is usually provided with auxiliary devices like chute blocks and dentated sills for the basic purpose of reducing the length of the stilling basin from about ________________

________________ are used only for very minor works.

Which of the following gate is not suitable for smaller spillways?

The percentage of energy dissipation in a hydraulic jump increases with the increase in the Froude number.

When the crest of an ogee spillway is designed to be in accordance with the lower nappe of a free-falling water jet over a duly ventilated sharp-crested weir then theoretically

Which of the following stilling basin help in stabilizing the flow and improve the jump performance?

Which of the following helps in dissipating the residual energy and to reduce the length of the jump or the basin?

A siphon spillway is sufficiently independent of the water surface elevation of the reservoir.

Which of the following stilling basin is applicable to only rectangular cross-sections?

If a flood enters a dam reservoir at F.R.L, the efficiency of its ogee spillway will ______________

The device which does not help in energy dissipation at the bottom of a hydraulic structure over which water spills is ________________

In the functioning of an ogee spillway, the operating head ______________________

The structure which is not used in a shaft spillway is ________________

If the operating head on an ogee spillway is more than the design head then ________________

Which of the following gate works on the principle of counterweights against the water pressure?

The W.E.S downstream profile of an ogee spillway can be represented by an equation:Xⁿ = K Hdⁿ⁻¹. YWhere x and y are the coordinates of the points on the crest profile and K and n for a vertical upstream spillway would respectively be___________________

In the vertical Stoney spillway gate, the rollers are placed between the ______________

Morning glory is the _____________________________

The spillway gate which when lowered cannot be seen from a distance is of the type ______________________

What is the expected solution for the case when the T.W.C is lying above the J.H.C curve at all discharges?

An air vent is provided at FRL to break the siphoning action at that level in a ___________________

A troublesome and oscillating hydraulic jump is normally met in cases of _____________

The spillway which can be adopted with ease on gravity as well as earthen dams is _________________