# 190+ Water Supply Engineering Solved MCQs

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1.

## The size of suspended solids lies in the range of

A. 10-3 – 10-6 mm
B. 103 – 106 mm
C. 10-1 – 10-3 mm
D. 101 – 103 mm
Answer» C. 10-1 – 10-3 mm
Explanation: size of suspended solids – 10-1
2.

## Suspended solids are measured by which of the following?

A. turbidity rod
B. gravimetric test
C. chromatography
D. jackson’s turbidity meter
Explanation: turbidity rod and jackson’s turbidity meter is used to find turbidity whereas chromatography is used to detect odour. hence b is the correct answer.
3.

## The maximum permissible limit for suspended solids is

A. 10 mg/l
B. 20 mg/l
C. 30 mg/l
D. 40 mg/l
Explanation: the maximum permissible limit for suspended solids is 30mg/l for
4.

## Identify the correct relation between the following?

A. dissolved solid = total solid + suspended solid
B. dissolved solid = total solid – suspended solid
C. total solid = dissolved solid / suspended solid
D. dissolved solid = suspended solid – total solid
Answer» B. dissolved solid = total solid – suspended solid
Explanation: dissolved solid is the difference between total solid and suspended solid. suspended solid is non-filterable solid whereas dissolved solid is filterable solid.
5.

## Which method is used to measure the color of water?

A. gravimetric analysis
B. chromatography
C. tintometer method
D. hydrometer analysis
Explanation: the colors in water are measured by tintometer method. it is measured on burgess scale or cobalt scale by nessler’s tube.
6.

## 1 TCU (True Color Unit) is equivalent to

A. the color produced by 1 g of platinum cobalt
B. the color produced by 1 mg of platinum cobalt
C. the color produced by 1 mg of platinum cobalt in 1l of distilled water
D. the color produced by 1 mg of platinum cobalt in 1ml of distilled water
Answer» C. the color produced by 1 mg of platinum cobalt in 1l of distilled water
Explanation: 1 tcu (true color unit) is equivalent to color produced by 1 mg of platinum cobalt in 1l of distilled water. the true color unit is also called a hazen unit.
7.

## Threshold odour number testing is preferred in hot water.

A. true
B. false
Explanation: ton testing is preferred in cold water as in hot water due to increase in temperature, taste and odour can change.
8.

## One JTU is equivalent to turbidity produced by

A. 1mg of fine silica dissolved in 1l of distilled water
B. 1g of fine silica dissolved in 1l of distilled water
C. 1g of fine silica dissolved in 1ml of distilled water
D. 1mg of fine silica dissolved in 1ml of distilled water
Answer» A. 1mg of fine silica dissolved in 1l of distilled water
Explanation: 1 jtu is equivalent to turbidity produced by 1mg of fine silica dissolved in 1l of distilled water. it is called as jackson’s turbidity unit and is based on the absorption principle.
9.

## If the PO value is 6, what does it imply?

A. no perceptible odour
B. very faint odour
C. very distinct odour
D. extremely strong odour
Explanation: the po value indicates the odour intensity. 6 is the maximum po value and it indicates extremely strong odour.
10.

## The permissible limit of turbidity of domestic water is          ppm.

A. 5-10
B. 1-5
C. 10-50
D. 10-30
Explanation: according to who, the permissible limit for drinking water is 5ntu.
11.

## What is the full form of NTU in context with turbidity?

A. number of transfer unit
B. neurological turbidity unit
C. nephelometric turbidity unit
D. network terminal unit
Explanation: the value of turbidity measured by nephelometer is expressed in terms of ntu. sometimes, it is referred as ftu or formazin turbidity unit.
12.

## When depth of insertion of turbidity rod increases, the reading in the turbidity rod

A. decreases
B. increases
C. first decrease, then increase
D. remains constant
Explanation: turbidity rod is inserted inside the water and the reading at which needle becomes invisible gives the turbidity.
13.

## The average quantity of water (in lpcd) required for domestic purposes according to IS code is

A. 100
B. 120
C. 70
D. 135
Explanation: the average domestic water demand in india is 135 litres per capita per day. for developed countries, average domestic water demand is around 340 lpcd because they live a luxurious life.
14.

## The average consumption of water required in factories in lpcd is

A. 10-15
B. 20-30
C. 30-45
D. 70-80
Explanation: the average water consumption in factories is 30lpcd when no bathrooms are required and 45lpcd when bathrooms are required.
15.

## In which type of water demand, minimum average consumption of water takes place?

A. domestic water demand
B. industrial water demand
C. institutional and commercial water demand
D. fire demand
Explanation: the minimum average water consumption takes place in fire demand. it accounts to 1lpcd which is very less but this water is required in very less duration.
16.

## Water lost in theft and waste contributes to how much % of total consumption?

A. 5
B. 10
C. 15
D. 20
Explanation: water loss in thefts and wastes contributes to 15% of total consumption, which includes the water loss due to leakage or stolen due to illegal connection.
17.

## What is the fire demand of the city of 1lakh population by Buston’s formula?

A. 5663
B. 56630
C. 566300
D. 5663000
Explanation: by buston’s formula, q = 5663√p where p in thousands. here, p =100, q = 5663√100 => q = 56630.
18.

## What are the factors affecting per capita demand?

A. size of city
B. size of city, habit of people
C. cost of water, quality of water, size of city
D. cost of water, quality of water, size of city, habit of people
Answer» D. cost of water, quality of water, size of city, habit of people
Explanation: increase in cost of water, quality of water and size of the city will result in more consumption of water. poor habits of people in the utilization of water will also cause greater consumption.
19.

## Which of the following statement is correct?

A. rich class consumes less water
B. intermittent water supplies leads to less water consumption
C. loss of water is more if the pressure in the distribution system is less
D. water consumption is less in flush system
Explanation: rich class consumes more water, loss of water is more if the pressure in distribution system is more, water consumption is more in flush system and b option is the only correct statement.
20.

## If the annual average hourly demand of the city is 10000m3, what is the maximum hourly consumption?

A. 2700 m3
B. 27000 m3
C. 270000 m3
D. 2700000 m3
Explanation: maximum hourly demand = 2.7
21.

## If in a city, the maximum daily draft is 25MLD, fire draft is 35MLD and maximum hourly draft is 40MLD, what is the coincident draft?

A. 60mld
B. 40mld
C. 25mld
D. 35mld
Explanation: maximum daily draft +fire draft = 25 + 35 = 60mld
22.

## What is the design period for the water treatment unit?

A. 10 years
B. 15 years
C. 20 years
D. 30 years
Explanation: water treatment unit is designed for 15 years and its design discharge is maximum daily demand.
23.

## What is the design discharge for intake structures?

A. maximum daily demand
B. maximum hourly demand
C. maximum weekly demand
D. average daily demand
Explanation: intake structures and the pipe mains that carry water from intake structures to treatment plant are designed for maximum daily demand.
24.

## In which of the following units, design period is maximized?

A. distribution system
B. demand reservoir
C. water treatment unit
D. pipe mains
Explanation: distribution system is designed for 30 years, the demand reservoir for 50 years, the water treatment unit for 15 years and the pipe mains for 30 years.
25.

## A hydel power project has been envisaged to serve the water supply and irrigation needs of the area at its inception stage. The dam reservoir so constructed is known as

A. multipurpose reservoir
B. single-purpose reservoir
C. distribution reservoir
D. retarding reservoir
Explanation: a reservoir planned and constructed to serve various purposes together is a multipurpose reservoir. it is designed to protect the downstream areas from floods, to conserve water, irrigation, industrial needs, hydroelectric purposes, etc. bhakra dam and nagarjuna sagar dam are important multipurpose dams.
26.

## Which reservoir is also known as Mitigation reservoir?

A. conservation reservoir
B. flood control reservoir
C. multipurpose dam
D. storage reservoir
Explanation: a flood control reservoir protects the downstream areas by storing a portion of the flood flows to minimize the flood peaks. the entire inflow entering the reservoir is discharged or gradually released to recover the capacity for the next flood. it is also called as a mitigation reservoir.
27.

## A reservoir having gates and valves installation at its spillway and at its sluice outlets

A. storage reservoir
B. retarding basin
C. both storage and retarding reservoir
D. distribution reservoir
Explanation: storage reservoir is the one having gates and valves installed at its spillway and at its sluice outlets whereas retarding basin is the one with uncontrolled and ungated outlets. it provides more flexibility in operation and better control.
28.

## Which reservoir is helpful in permitting the pumps or the water treatment plants to work at a uniform rate?

A. storage reservoir
B. detention reservoir
C. multipurpose reservoir
D. distribution reservoir
Explanation: a small storage reservoir constructed within a city water supply system
29.

## In which of the following reservoir the flood crest downstream can be better controlled and regulated properly?

A. distribution reservoir
B. multipurpose reservoir
C. storage reservoir
D. retarding reservoir
Explanation: storage reservoirs are preferred on large rivers and require better control. it is provided with gated spillway and sluiceways for more flexibility of operation, better control and to increase the usefulness of the reservoir.
30.

## What are the types of flood control reservoirs?

A. multipurpose reservoir and single purpose reservoir
B. storage reservoir and retarding reservoirs
C. distribution reservoir and storage reservoir
D. distribution reservoir and multipurpose reservoir
Answer» B. storage reservoir and retarding reservoirs
Explanation: there are two basic types of flood-mitigation reservoirs i.e. storage reservoir and retarding reservoirs. storage reservoir is the one having gates and valves installed at its spillway and at its sluice outlets whereas the retarding basin is the one with uncontrolled and ungated outlets.
31.

## As the reservoir elevation increases, the outflow discharge increases.

A. true
B. false
Explanation: when floods occur the reservoir gets filled and discharges through sluiceways and the water level goes on rising
32.

## The maximum discharging capacity of a retarding reservoir should not be equal to the maximum safe carrying capacity of the channel downstream.

A. true
B. false
Explanation: since the retarding reservoir is not always filled much of the land below the maximum reservoir level will be submerged only temporarily and occasionally. the automatic regulation of outflow depends upon the availability of water. the maximum discharging capacity should be equal to the maximum safe capacity of the channel d/s.
33.

## Which of the following can be identified as the objective of water supply scheme?

A. chlorination of water
B. treat water
C. safe water supply
D. ionization of water
Explanation: in general, the objective of water supply scheme includes safe water supply, sufficient quantity of water, supply of water to a convenient point with reasonable cost and encouraging personal and house hold cleanliness of the users.
34.

## Surface water can act as a source of water in water supply scheme.

A. true
B. false
Explanation: the source of water is classified as surface water and sub surface water. generally in the water supply scheme surface water is having more priority than the sub surface water. the different sources of surface water include river, streams, lakes, canals etc.
35.

## While considering the design period, which must be given more priority?

A. area of land
B. population
C. usage of water
D. arrangement of pipes
Explanation: design period is considered based on the population present in a particular area. while considering design period, population forecast methods has to be used for the determination of the upcoming population in that area. by doing this the design period can be estimated for a particular water tank construction.
36.

## Which of the following can be designated as an intake structure?

A. culvert
B. river
C. dam
D. reservoir
Explanation: intakes are the structures which can collect water from the surface sources and are used for the treatment plant.
37.

## Which type of water is generally used in the treatment of water?

A. chlorinated water
B. treated water
C. raw water
D. sulphated water
Explanation: water treatment plant generally uses raw water which is obtained from different sources containing various impurities. it is not recommended to be used directly without treatment and hence it is supplied to the treatment plant for treatment.
38.

## Which of the following does not act as a major factor that effects per capita demand?

A. human activity
B. industrial activities
C. usage of water
D. placement of pipe
Explanation: the factors effecting per capita demand include cost of water, climatic condition, pressure in the distributed system, industrial activities, commercial activities and economical status of the consumers.
39.

## The amount of water required for 1 percent per day is determined as

A. daily demand
B. monthly demand
C. annual demand
D. per capita demand
Explanation: per capita demand can be defined as the amount of water required for 1 percent per day. it includes commercial, industrial, domestic, public uses and also in case of fire demand.
40.

## Which of the following can act as a type of variation in water demand?

A. monthly variation
B. annual variation
C. crop variation
D. 10 year variation
Explanation: variation in water demand is generally due to seasonal variation, monthly variation, daily and hourly variations. the demand for water in these variations is generally high and consumes more amount of water than daily consumption.
41.

## The Clean Water Act (CWA) regulates

A. discharge of pollutants into the waters of the united states
B. discharge of pollutants into the waters of the united kingdom
C. discharge of pollutants into the air of the united states
D. discharge of pollutants into the waters of india
Answer» A. discharge of pollutants into the waters of the united states
Explanation: under the cwa, epa has implemented pollution control programs, such as setting wastewater standards for industry and water quality standards for all contaminants in surface waters.
42.

## Section                      of CWA regulates discharges of hazardous substances.

A. 311(b)(2)(b)
B. 311(b)(2)(a)
C. 312(b)(2)(a)
D. 311(b)(1)(a)
Explanation: section 311(b)(2)(a) of cwa regulates discharges of hazardous substances, which also includes formaldehyde. the list of designated hazardous substances is found at 40 cfr 116.4.
43.

## The CWA made it unlawful to discharge any pollutant from a point source into navigable waters, unless a permit was obtained.

A. true
B. false
Explanation: epa’s national pollutant discharge elimination system (npdes) permit program controls discharges.
44.

## The Federal Water Pollution Control Act of 1948 was the first major U.S. law to address water pollution.

A. 1945
B. 1946
C. 1947
D. 1948
Explanation: the federal water pollution control act of 1948 grew public awareness
45.

## The Federal Water Pollution Control Act of 1948 became CWA.

A. false
B. true
Explanation: the federal water pollution control act of 1948 was the first key u.s. law to address water pollution, it was amended in 1972 and the law clean water act (cwa).
46.

## The CWA reduced the amount of pollution from

A. point sources
B. non-point sources
C. chemicals
D. mining
Explanation: the clean water act has been accredited with pointedly reducing the amount of pollution that enters the u.s. waterways from point sources, municipal and industrial discharges.
47.

## The discharge of regulated chemicals into surface waters is controlled by

A. sara
B. cercla
C. npdes
D. pdac
Explanation: the discharge of regulated chemicals into surface waters is controlled by the national pollutant discharge elimination system (npdes) which entails contaminators to obtain federal permits for each chemical they discharge.
48.

## The maximum amount of pollution that each waterway could absorb is known as

A. tmdl
B. tsml
C. tdsml
D. tds
Explanation: the tmdl establishes a target for total load of pollutant the water body can assimilate and allocates the load to point sources which are known as the waste load allocation and nonpoint sources known as the load allocation.
49.

## requires EPA to establish regulations to protect human health from contaminants present in drinking water.

A. sawd
B. sdwa
C. asaw
D. swsa
Explanation: the safe drinking water act (sdwa) permits epa to develop national drinking water standards and safeguard agreement with these standards, and guides epa to protect underground sources of drinking water through the regulation of underground injection of fluids to prevent pollution.
50.

## Who is responsible for the clean-up of oil spill?

A. hws
B. aps
C. oil pollution act
D. sara
Explanation: the cwa and the oil pollution act provide federal authority to prevent, respond to and clean up an oil spill or the threat of an oil spill.
51.

## Which section of CWA regulates land disposal of sludge?

A. section 402
B. section 403
C. section 404
D. section 405
Explanation: section 405 of the cwa regulates the land application and the land disposal of sludge – the solid, semisolid or liquid untreated residue generated during the treatment of domestic sewage in a treatment facility.
52.

## Which CWA program controls water pollution by regulating point sources?

A. spcc
B. pcc
C. npdes
D. pda
Explanation: the npdes program controls
53.

## Which section of CWA is responsible for monitoring of wetlands?

A. section 402
B. section 403
C. section 404
D. section 405
Explanation: section 404 of the cwa establishes a program to regulate the discharge of dredged or fill material into waters of the united states, including wetlands.
54.

## Which CWA program manages non-point source pollution?

A. npsmp
B. nsppp
C. nsgop
D. npsra
Explanation: the cwa under section 319 established the nonpoint point source (nps)
55.

## The design period of storage reservoir can be given as

A. 50 yr
B. 20 yr
C. 30 yr
D. 10 yr
Explanation: every water storage structure is having certain design periods based on the population present in that particular area. a storage reservoir is generally having a design period of 50 years.
56.

## Which material is used for pipes which are in contact with milk or product?

A. stainless steel
B. copper
C. ceramic
D. plastic
Explanation: all components in contact with the product are made of stainless steel.
57.

## Which material is used for pipes which conduct water and air?

A. stainless steel
B. copper
C. ceramic
D. plastic
Explanation: plastic is used for water and air lines. plastic also provides transparency.
58.

## Which material is used for pipes which conduct waste?

A. stainless steel
B. copper
C. ceramic
D. plastic
Explanation: various materials are used in the other systems, e.g. cast iron, steel, copper and aluminum. plastic is used for water and air lines, and ceramic for drainage and sewage pipes.
59.

## Which of the following are installed in order to collect product samples hygienically for quality analysis?

A. bends
B. reducers
C. sampling device
D. tees
Explanation: sampling devices need to be installed at strategic points in the plant to collect product samples for analysis. for quality control, such as determining the fat content of milk and the ph value of cultured products, the samples can be collected from a sampling cock.
60.

## Which among the following is not a permanent wielding connection?

A. bends
B. reducers
C. sampling device
D. tees
Explanation: some examples of fittings for permanent welding are tees, reducers and bends. this union allows disconnection without disturbing other pipe work. this type of joint is hence used to connect process equipment, instruments, etc. that need to be removed for cleaning, repair or replacement.
61.

## Calculate area of a pipe if, flow rate is 20 l/min and flow velocity is 5 cm/s.

A. 66.66 cm2
B. 60 cm2
C. 62 cm2
D. 64 cm2
Explanation: flow rate = 20 litre/min
62.

## Which formula is used to calculate head loss in valves?

A. k2 (v/2 g)
B. k (v/2 g)
C. k (v2/2 g)
D. k3 (v2/2 g)
Explanation: k (v2/2 g) calculates head loss for newtonian fluid. when fluid flows inside a pipeline, friction occurs between the moving fluid and the stationary pipe wall.
63.

## Which among the following is shut-off and change over valve?

A. seat valve
B. butterfly valve
C. seat valve and butterfly valve
D. bend
Answer» C. seat valve and butterfly valve
Explanation: there are many places in a piping system where it must be possible to stop the flow or divert it to another line.
64.

## To prevent the product flow in the wrong direction which of the following valve is used?

A. seat valve
B. butterfly valve
C. seat valve and butterfly valve
D. check valve
Explanation: a check valve is fitted when it is necessary to prevent the product from flowing in the wrong direction. the valve is kept open by the liquid flow in the correct direction. if the flow stops, the valve plug is forced against its seat by the spring. the valve then closes against reversal of the flow.
65.

## The pipes will expand considerably when the product temperatures are high and during cleaning.

A. true
B. false
Explanation: pipes must be firmly supported. on the other hand the pipes should not be so restrained that movement is prevented. the pipes will expand considerably when the product temperatures are high and during cleaning. the resulting increase in length and tensional forces in bends and equipment must be absorbed.
66.

## Valves with constant outlet pressure are used after which of the following machines?

A. separator
B. pasteurizer
C. homogenizer
D. filling machine
Explanation: valves for constant inlet pressure are often used after separators and pasteurizers. those for constant outlet pressure are used before filling machines.
67.

## What is the total loss developed in a series of pipes?

A. sum of losses in each pipe only
B. sum of local losses only
C. sum of local losses plus the losses in each pipe
D. zero
Answer» C. sum of local losses plus the losses in each pipe
Explanation: when the pipes of different diameters are connected in series from end to end to form a pipe line. the total loss so developed is equal to the sum of local losses plus the losses in each pipe. the local losses are developed at the connection point.
68.

## The total head loss for the system is equal to

A. pipe length
B. pipe diameter
C. width of the reservoir
D. height difference of reservoirs
Answer» D. height difference of reservoirs
Explanation: total head loss for a system is equal to the height difference of the reservoirs. height difference is denoted by the letter ‘h’. total head loss can be equated by summing it up with all the local losses and the losses at each pipe.
69.

## Which among the following is not a loss that is developed in the pipe?

A. entry
B. exit
C. connection between two pipes
D. liquid velocity
Explanation: liquid velocity in the pipe is the velocity with which the liquid travels through different cross sections of the pipe. it is a vector field which is used to describe the motion of a continuum. the length of flow velocity vector is equal to the flow speed.
70.

## Which among the following is the correct formula for head loss?

A. z1-z2
B. c
C. t2-t1
D. s2-s1
Explanation: total head loss for a system is equal to the height difference of the reservoirs. height difference is denoted by the letter ‘h’. total head loss can be equated by summing it up with all the local losses and the losses at each pipe. here, the height difference between the reservoirs is z1-z2.
71.

## If the two reservoirs are kept at the same level, the head loss is

A. z1-z2
B. zero
C. t2-t1
D. s2-s1
Explanation: total head loss for a system is equal to the height difference of the reservoirs. height difference is denoted by the letter ‘h’. the height difference between the reservoirs is z1-z2. since they are of the same level, z1=z2. therefore, head loss is zero.
72.

## How do we determine the total discharge through parallel pipes?

B. subtract them
C. multiply them
D. divide them
Explanation: total discharge in parallel pipes are determined by adding the discharges so developed in individual pipes. if q1 is the discharge through pipe 1 and q2 is the discharge through pipe 2. then the total discharge through parallel pipes is equal to q1+q2.
73.

## The pipe diameter is

A. directly proportional to fluid density
B. directly proportional to mass flow rate
C. inversely proportional to mass flow rate
D. directly proportional to fluid velocity
Answer» B. directly proportional to mass flow rate
Explanation: the pipe diameter is directly proportional to mass flow rate of fluid. pipe diameter can be calculated if volumetric flow rate and velocity are known. ‘d’ is inversely proportional to its velocity.
74.

## Define Viscosity.

A. resistance to flow of object
B. resistance to flow of air
C. resistance to flow of fluid
D. resistance to flow of heat
Answer» C. resistance to flow of fluid
Explanation: viscosity is developed due to the relative motion between two surfaces of fluids at different velocities. it happens due to the shear stress developed on the surface of the fluid.
75.

## Coefficient of friction of a laminar flow is

A. re/16
B. re/64
C. 16/re
D. 64/re
Explanation: coefficient of friction is defined as the value that shows relationship between force and the normal reaction. it is mainly used to find out an object’s normal
76.

## What is the aim of pipes system in the dairy industry?

A. facilitate product flow
B. pasteurization
C. fouling
D. storage
Explanation: the product flows between the components of the plant in the pipe system. a dairy also has conduit systems for other media such as water, steam, cleaning solutions, coolant and compressed air.
77.

## 4 LAYING, JOINTING AND TESTING OF PIPES - APPURTENANCES

A. stainless steel
B. copper
C. ceramic
D. plastic
Explanation: various materials are used in the other systems, e.g. cast iron, steel, copper and aluminum. plastic is used for water and air lines, and ceramic for drainage and sewage pipes.
78.

## Which grade of stainless steel is known as acid proof steel?

A. aisi 304
B. aisi 316
C. sis 2333
D. sis 2359
Explanation: for hygienic reasons, all product-wetted parts of dairy equipment are made of stainless steel. two main grades are used, aisi 304 and aisi 316. the latter grade is often called acid proof steel.
79.

## Which of the following valves is used to maintain pressure in the system?

A. pressure relief valve
B. check valve
C. manual control valve with variable flow plug
D. pneumatic control valve with variable-flow plug
Explanation: a pressure relief valve maintains the pressure in the system. if the pressure is low, the spring holds the plug against the seat. when the pressure has reached a certain value, the force on the plug overcomes the spring force and the valve opens.
80.

## Which of the following pump is based on the type of power?

A. low lift pump
B. high lift pump
C. air lift pump
D. steam engine pump
Explanation: there are 3 types of pumps on the basis of type of power. they are – steam engine, diesel engine and electrically driven pump.
81.

## Displacement pump is classified on the basis of

A. mechanical operation of principle
B. type of power
C. type of service
D. efficiency
Answer» A. mechanical operation of principle
Explanation: mechanical principle of operation is classified into displacement, centrifugal, air lift and miscellaneous pumps.
82.

## Which of the following pump is classified based on the type of service?

A. displacement pump
B. centrifugal pump
C. deep well pump
D. electric driven pump
Explanation: pumps are of four types on the basis of type of service- low lift, high lift, deep well and booster pump.
83.

## The centrifugal pump has a              flow.

A. variable
B. uniform
C. continuous
D. constant
Explanation: the centrifugal pump has a
84.

## The speed at which the centrifugal pump runs (in r.p.m) is

A. 200
B. 300
C. 500
D. 1200
Explanation: the speed at which the centrifugal pump runs lies in the range of 500 to 100 rates per minute (r.p.m). the direct connection of pump with driving machines is possible.
85.

## The maximum efficiency of a centrifugal pump is

A. 50%
B. 60%
C. 85%
D. 100%
Explanation: the efficiency of the centrifugal pump lies between 40% and 85%. it depends on the head and discharge of the pump.
86.

## Based on the type of casing, the centrifugal pump is divided into            types.

A. 2
B. 3
C. 4
D. 5
Explanation: based on the type of casing, the centrifugal pump is divided into the volute pump and turbine pump.
87.

## pumps produce a head and a flow by increasing the velocity of the liquid with the help of the rotating vane impeller.

A. displacement pumps
B. positive pumps
C. centrifugal pumps
D. rotating pumps
Explanation: centrifugal pumps produce a head and a flow by increasing the velocity of the liquid with the help of the rotating vane impeller. centrifugal pumps include radial, axial and mixed flow units.
88.

## What are the pumps that operate by alternately filling a cavity and then displacing a given volume of liquid called?

A. centrifugal pump
B. rotating pump
C. positive displacement pump
D. roto-dynamic pump
Explanation: a positive displacement pump alternately fills a cavity and then displaces a given volume of liquid. for each cycle, this pump delivers a constant volume of liquid independent of discharge pressure or head.
89.

## The two types of pumps behave very differently regarding pressure head and flow rate.

A. true
B. false
Explanation: there are two types of basic pumps. one is the centrifugal pump and the other one is positive displacement pump.
90.

## A steam pump is a type of centrifugal pump.

A. true
B. false
Explanation: there are different types of centrifugal pumps such as end suction pumps, in-line pumps, axial-flow pumps, regenerative pumps, etc. steam pump is a type of positive displacement pump.
91.

## What are the pumps with one or more impellers called?

A. ansi process pumps
B. api process pumps
C. centrifugal pumps
D. positive displacement pumps
Explanation: the general name for pumps with one or more impellers is called centrifugal pumps. many types and configurations of centrifugal pumps are used for different applications.
92.

## Why are booster pumps used?

A. higher flow
B. boost pressure
C. chop solids
D. maintain flow
Explanation: booster pumps are used to further boost the pressure in a system. it may be in-line circulator, horizontal split case, or vertical turbine in a can type of pump.
93.

## Why are cryogenic pumps used?

A. boost pressure
B. handle low temperature liquids
C. handle high temperature liquids
D. pump small quantities of liquids
Answer» B. handle low temperature liquids
Explanation: cryogenic pumps are used to handle very low temperature liquids. booster pumps are used to further boost the pressure in a system. drum pumps are used to pump out small quantities of liquid of out of drums and carboys.
94.

## End suction pumps are the common type of                    pumps.

A. drum pumps
B. centrifugal pumps
C. positive displacement pumps
D. grinder pumps
Explanation: end suction pumps are the common type of centrifugal pump. it has a horizontal shaft with an overhung impeller. the flow goes in the end of the casing, and out the top.
95.

## Which pump among the ones mentioned below can be located above the suction reservoir without an external priming system?

A. slurry pumps
B. self-priming pumps
C. submersible pumps
D. trash pumps
Explanation: self-priming pumps are a type of centrifugal that can be located above the suction reservoir without an external priming system. it has an end suction configuration but an enlarged case to support priming.
96.

## Which type of pump is designed to handle rocks and other solids?

A. trash pumps
B. submersible pumps
C. slurry pumps
D. self-priming pumps
Explanation: trash pumps are a type of submersible centrifugal pump designed to handle rocks and other solids while dewatering. it is used in dewatering construction sites, mines, and utility pits.
97.

## Which type of pump should be used in order to handle low viscosity fluids?

A. centrifugal pump
B. displacement pump
C. submersible pump
D. end suction pump
Explanation: centrifugal pumps can pump liquids which are of low viscosity. it cannot handle liquids such as oil. the liquid that is pumped by centrifugal pumps should be free from air.
98.

## Which type of pump should be selected in order to pump the sewage from a septic tank to the water treatment system?

A. vertical sump pump
B. progressive cavity pump
C. submersible pump
D. screw pump
Explanation: submersible pumps are used to handle liquids with solids. also, these are non-clog pumps which are fully or partially submerged in the tanks. in cases where the pump is partially submerged the motor is above the water level and the motor is connected to the pump by an extended shaft.
99.

## In an activated sludge process which type of pump is used to recirculate the sludge?

A. booster pump
B. centrifugal pump
C. vane pump
D. vertical turbine pump
Explanation: the activated sludge does not contain any solids. also, it is not very viscous. hence a centrifugal pump can be used for this application.
100.

## Which type of pump is used while handling the sludge disposal system?

A. screw pump
B. multistage pump
C. self-priming pump
D. vertical pump