1. Normally about _________ percent of the per
capita consumption of water becomes wastewater.
a)
90-95%
b) 80-90%
c)
60-70%
d)
95-99%
2. Considering 200 litre per capita water
consumption and sewage flow of 80%, the per capita flow will be ________
litre/capita/day.
a)
190lpcd
b)
180lpcd
c)
170lpcd
d) 160lpcd
3. The peak factor
shall not be greater than __ and not less than __ in any case.
a)
4 and 2
b) 6 and 2
c)
10 and 5
d)
1 and 0
4. Sewerage network will be designed for the
_______ flow.
a)
Avg. Flow
b)
Uniform flow
c) Peak flow
d)
None
5. Minimum self
cleansing velocity is ___m/sec. under flowing full condition. Preferably it is
taken as ___ m/sec for the designing of the system. Maximum velocity will not
be greater than ___ m/sec.
a) 0.6 ,0.75 ,2.4
b)
0.5, 0.6, 2.0
c)
0.6, 1, 2.4
d)
1, 2, 4,
e) 0.75,
1, 2.4
6.
The minimum slope for a section of sewer will generally be based on the ______
velocity requirements.
a)
Max velocity
b) Min velocity
c)
Avg velocity
d)
Peak velocity
7.
Sewers will be designed to flow at _____of full depth under peak flow
conditions to provide requisite air gap.
a)
0.9
b)
0.6
c) 0.75
d)
0.8
8.
Thus the design flow will be calculated by multiplying peak flow with a factor
of 1.12.
a)
1.5
b)
1.2
c) 1.12
d)
2
9.
Minimum sewer pipe size will be ______ mm except for house connections which
will be ___ mm.
a)
150 and 200
b)
100 and 200
c) 200 and 150
d)
200 and 100
10.
The type of pipes to be used for sewerage system depends upon the following
factors:
a)
Corrosion resistance
b)
Capital cost
c)
Local availability
d) All of the above
11. ____
pipes will be used for sewer lines. For house connections _____ pipes will be
used.
a)
UPVC , HDPE
b) HDPE, UPVC
c)
VC , PVC
d)
BOTH UPVC
12.
In order to provide
building connections, minimum earth cover over the pipes will be __ m.
a) 0.5
b)
1
c) 2
d)
2.5
13.
trench width for the pipe of dia 200 mm is:
a)
600 mm
b) 700 mm
c)
750 mm
d)
500 mm
14.
Manholes will be located according to conventional sewer network design i.e.
a)
at starting points,
b)
junctions between sewers (except building
connections to sewers),
c)
changes in direction and grade,
d) all of the above.
15.
the manhole spacing for 300 to 600mm dia pipes is:
a)
Less than 50m
b) 50 to 80 m
c)
>100
d)
>150
16.
For sewer lines up to 700 mm diameter manholes will have a circular chamber of __metre
internal diameter.
a)
1m
b)
2m
c)
1.5m
d) 1.2m
17.
To minimize the risk of blockage in sewers, the diameter of the outgoing sewer
must not be ____ than the diameter of the largest incoming sewer.
a)
Greater
b) Less
c)
Equal
d)
None
18.
The _____connections to manholes will be provided if the difference in pipe
invert elevation is greater than 600 mm
a)
Fixed
b) Drop
c)
Loose
d)
Elevated
19.
Connection pipes will be ___ mm diameter or greater depending on the population
of the buildings and the available grade.
a)100
b) 150
c) 200
d) 250
20. The proposed sewage treatment plant will be based
on
a) extended aeration,
b)
activated sludge process.
c)
Both
d) Only b
21. The rated capacity of the plant will be
average ______ sewage flow.
a)
Annual daily
b) Annual hourly
c) Peak flow
d) Annual avg.
22. The substances which hinder the biological
processes are classified as follows:
a.
Fats, oils and grease
b.
Priority pollutants
c.
Both
d.
Only fats
23. Average sewage temperature for the coolest
month will be adopted as design temperature which is taken as ____°C.
a) 25
b) 30
c) 50
d)
20
24. depth of
circular clarifiers is:
a) 3-6m
b)
4-6
c) 5m
d) 6m
25. The dewatered sludge through drying beds
will be transported through vehicles and disposed off at landfill site; the
site should be of sufficient capacity to store the sludge minimum for ___ days.
a)
100
b) 150
c) 365
d) None
26.______and well water generally do not need
further purification.
a)
Spring
b) River
c) Rain water
d) Ground water
27. which is not true for the water
distributions system.
a) Delivers water from the pumping station
throughout the area.
b)
Dead-end hydrant
receives water from many direction
c) Circulating-feed hydrant receives water from
two or more directions
d) Grid systems provide circulating feed from
several mains
28. recommended pipe sizes for main streets
a)
12”
b) 10”
c) 8”
d) 6”
29. recommended pipe sizes for business and
industrial.
a) 12”
b) 4”
c) 6”
d)
8”
30. recommended
pipe sizes for residential;
a) 12”
b) 8”
c)
6”
d) 4”
31. The term used for raising static water to
supply a pumper
a) Lifting
b) Elevating
c)
Drafting
d) Accelerating
32. water distribution system consists of:
a) Pipe networks
b) Measurements ( Discharge & pressure)
c) Manifolds and diffusers
d) Both a and c
e)
All of the above
33. Each point in
the system can only have one pressure
a) One pressure
b) Equal pressure
c) different pressure
d)
both a and b
34. Valve will begin to open when the pressure greater is
upstream than the sets-point pressure.
a) Pressure reducing valve
b) Pressure regulating valve
c)
Pressure sustaining
valve
d) None
35. Commonly used to limit the maximum flow to
a value that will not adversely affect the provider’s system
a) Pressure reducing valve
b) Pressure regulating valve
c) Pressure sustaining valve
d)
Flow control valve
36. Purposes for Storage
a.
To balance supply and demand
b.
Protection against breakdown
c.
To provide a static head for gravity running
d.
Water treatment.
e. All of the above
37. there are ____ categories of pipe.
a)
2
b)
3
c)
4
d) 5
38. They have relatively large diameter and
are used for conveyance and distribution.
Materials used include cast iron, spun iron, asbestos, cement, or steel.
a)
main
b) Service
c) Plumbing
d) None
39. pipe work within the building is included
in __________ categories.
a) main
b) Service
c)
Plumbing
d) None
40. There are three important pressures
associated with pipes.
a)
Work Test:
b)
Maximum Field Test
c)
Maximum Working
Pressure
d)
All of above
41. Energy cost is a function of head losses
while pipe cost is a function of diameter.
a) Thickness
b) Length
c)
diameter
d) all of the above
42. Allow ___ m (for big pipes) to ___ m
(small pipes) head loss per 1000 m of mainline
a) 1 and 10
b)
2 and 5
c)
2 and 10
d)
1 and 2
43.
Normal
practice in water supply for irrigation is to keep velocity within 0.6 to 1.5
m/s.
a)
0.6 to1
b)
0.5 to 1.5
c) 0.6 to 1.5
d)
0.75 to 1
44.
. Water hammer is transient high pressure waves
due to rapid valve closure
a)
Standing wave
b)
Water hammer
c)
Hydraulic jump
d) Both a and b
45.
Pipe
diameter can be chosen using head losses and velocity using charts or
equations.
a)
Slopes
b)
Lengths
c) Head losses
d)
None
46. branch
system is used in _______projects.
a)
Large community
b) Small community
c)
Rural areas
d)
None
47. _____________
water reaches to point from different directions in
a)
Grid system
b)
Looped network
c)
Branching systems
d) Both a and b
48. __________
has the disadvantages are that the designs are more complicated and there are
more pipes and more fittings.
a)
Grid system
b)
Looped network
c)
Branching systems
d) Both a and b
49. hf
= 10.67
CH -1.85 D- 4.87 Q1.85 L, where
CH is:
a) roughness coefficient of pipe material
b)
roughness coefficient of fluid
c)
pressure coefficient
d)
none
50.
Usually, flow velocities shall be ______
a) < 3 m/s
b)
< 2m/s
c)
< 1m/s
d)
< 0.75m/s
51. Water
storage allowance depends on:
a)
Type and use of buildings
b)
Storage capicity
c)
Both a and d
d)
Frequency and pattern of use
52. NPSH
stands for in pumps
a) Net positive suction head
b)
Negative pressure suction head
c)
Net positive storage head
d)
Negative pressure storage head
53. Capacity
varies with head- Capacity proportional to pump speed- Head proportional to the
square of pump speed- Non self-priming- Suitable for low-viscosity liquid are
the characteristics of _____________ pump.
a) Centrifugal pumps
b)
Reciprocating pump
c)
Positive displacement pump
d)
None
54.
Capacity substantially independent of head- Capacity proportional to speed-
Self-priming- Suitable for various liquids (reduced speeds usually necessary
for high viscosity are the characteristics of
a)
Centrifugal pumps
b) Reciprocating pump
c)
Positive displacement pump
d)
None
55. Pumps
connected in series:
a) Double the pressure
b)
Double the flow
c)
Double the head
d)
None
56. ______________Pumps
connected in parallel:
a)
Double the pressure
b) Double the flow
c)
Double the head
d)
None
57. At
sudden contractions, flow streamlines converge causing the downstream developed
flow to have an area smaller than the downstream pipe diameter. This flow constriction is called the___.
a)
Turbulence
b) Vena contracta
c)
Irregulation
d)
Current developement
