Explore topic-wise MCQs in Engineering.

This section includes 5814 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.

4301.

The design period in years for pumping plants, is

A. 1
B. 2 to 3
C. 3 to 5
D. 5 to 10
Answer» E.
4302.

The settlement velocity of a solid (diameter 0.5 mm, specific gravity 1.75) in water having temperature 10 C, is

A. 213.5 cm/sec
B. 313.5 cm/sec
C. 413.5 cm/sec
D. 500 cm/sec.
Answer» C. 413.5 cm/sec
4303.

The Chezy's constant C in the formula V = C rs depends upon

A. size of the sewer
B. shape of the sewer
C. roughness of sewer surface
D. hydraulic characteristics of sewer
E. all the above.
Answer» F.
4304.

Afive day B.O.D. at 15 C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15 C for standard sewage is 0.1 kg/day, the population equivalent is

A. 100
B. 1000
C. 5000
D. 10000
Answer» E.
4305.

Silt storage is the same as

A. dead storage
B. live storage
C. effective storage
D. none of these.
Answer» B. live storage
4306.

The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is

A. 0.05552 cumec
B. 0.05554 cumec
C. 0.05556 cumec
D. 0.0556 cumec
E. 0.0558 cumec.
Answer» D. 0.0556 cumec
4307.

For complete stabilisation of organic matter in polluted water, it takes

A. 5 days
B. 10 days
C. 20 days
D. 30 days
E. 40 days.
Answer» E. 40 days.
4308.

The maximum diameter of sewers adopted in the designs is

A. 1.0 m
B. 2.0 m
C. 3.0 m
D. 4.0 m.
Answer» D. 4.0 m.
4309.

Which one of the following statements regarding septic tanks is wrong :

A. a gap of 7.5 cm between the bottom of the covering slab and the top level of scum is provided
B. the outlet invert level is kept 5 to 7.5 cm below the inlet invert level
C. the minimum width of septic level is 90 cm
D. the depth of tank is kept equal to its width.
Answer» E.
4310.

Sluge banks are formed if sewage is disposed of in

A. rivers
B. seas
C. lakes
D. none of these.
Answer» C. lakes
4311.

Design period of 40 to 50 years is adopted for

A. branch sewers
B. main sewers
C. trunk sewers
D. all the above.
Answer» E.
4312.

The water carried sewerage system removes

A. domestic sewage
B. industrial sewage
C. storm sewage
D. all the above.
Answer» E.
4313.

PH value of sludge during alkaline regression stage, is

A. more than 7
B. less than 7
C. less than 6
D. more than 6.
Answer» B. less than 7
4314.

Ventilating shafts are provided to a sewer line at every

A. 100 m
B. 150 m
C. 200 m
D. 300 m
E. 500 m.
Answer» E. 500 m.
4315.

If the peak discharge of a storm water drain (S.W. Drain) is e.xpected to exceed 150 cumecs, the free board to be provided, is

A. 100 cm
B. 90 cm
C. 80 cm
D. 50 cm.
Answer» B. 90 cm
4316.

Depletion of ozone layer in the outer atmosphere may cause

A. lung cancer
B. skin cancer
C. bronchitis
D. heart disorder.
Answer» C. bronchitis
4317.

The spacing of bars of perforations of fine screens used for the treatment of sewage, is

A. 2 to 3 mm
B. 3 to 5 mm
C. 5 to 8 mm
D. 8 to 10 mm.
Answer» B. 3 to 5 mm
4318.

If n is the rugosity coefficient, r is the hydraulic depth, s is the bed slope of sewer, the velocity of flow in m/sec may be obtained by the formula evolved by

A. Chezy
B. Manning
C. Bazin
D. Kutter.
Answer» C. Bazin
4319.

rd or th extra space is left in sewer pipes at maximum discharge for

A. low estimates of the average and maximum flows
B. large scale infiltration of storm water
C. unexpected increase in population
D. all the above.
Answer» E.
4320.

Antisyphonage pipe is fitted

A. at the end of septic tanks
B. on manholes
C. with a W.C. trap
D. at the beginning of sewer line.
Answer» D. at the beginning of sewer line.
4321.

As compared to fresh river water, sea water contains oxygen

A. 10% less
B. 20% less
C. 10% more
D. 20% more.
Answer» C. 10% more
4322.

Drop manholes are the manholes

A. without entry ladders
B. without manhole covers
C. with depths more than 3.5 m
D. having drains at different levels.
Answer» E.
4323.

Skimming tanks are

A. used to remove the grease and oil
B. those from which sludge is skimmed out
C. tanks provided with self-cleansing screens
D. improved version of grit chambers.
Answer» B. those from which sludge is skimmed out
4324.

In sewers designed with self cleansing velocity,

A. the bottom is silted
B. the bottom is scoured
C. both silting and scouring occur at the bottom
D. neither silting nor scouring occurs at the bottom.
Answer» E.
4325.

In a sludge digestion tank if the moisture content of sludge V1 litres is reduced from p1 % to p2 % the volume V2 is

A. <img src="/_files/images/civil-engineering/waste-water-engineering/192-9.188-1.png">
B. <img src="/_files/images/civil-engineering/waste-water-engineering/192-9.188-2.png">
C. <img src="/_files/images/civil-engineering/waste-water-engineering/192-9.188-3.png">
D. <img src="/_files/images/civil-engineering/waste-water-engineering/192-9.188-4.png">
Answer» D. <img src="/_files/images/civil-engineering/waste-water-engineering/192-9.188-4.png">
4326.

Stoneware sewers are available in size

A. 10 cm
B. 15 cm
C. 20 cm
D. 25 cm
E. all the above.
Answer» F.
4327.

The sludge does not contain waste water from

A. bath rooms
B. wash basins
C. kitchen sinks
D. toilets.
Answer» E.
4328.

Boussinesq's equation for ascertaining unit pressure at a depth H on sewers due to traffic loads, is

A. <img src="/_files/images/civil-engineering/waste-water-engineering/184-9.71-1.png">
B. <img src="/_files/images/civil-engineering/waste-water-engineering/184-9.71-2.png">
C. <img src="/_files/images/civil-engineering/waste-water-engineering/184-9.71-3.png">
D. <img src="/_files/images/civil-engineering/waste-water-engineering/184-9.71-4.png">
E. none of these.
Answer» B. <img src="/_files/images/civil-engineering/waste-water-engineering/184-9.71-2.png">
4329.

Aerobic activity is maximum

A. in freshly produced sewage
B. at sewer pipes
C. in sewer treatment plants
D. none of these.
Answer» B. at sewer pipes
4330.

Stone ware pipes are

A. highly resistant to sulphide corrosion
B. highly impervious
C. hydraulically efficient because of their smooth interior surface
D. specially suited to pressure pipes
E. none of these.
Answer» E. none of these.
4331.

For detecting the nitrites in the sewage, the matching colour may be developed by adding

A. Pottassium permanganate
B. Sulphuric acid and napthamine
C. Phenol-di-sulphuric acid pottassium hydroxide
D. None of these.
Answer» C. Phenol-di-sulphuric acid pottassium hydroxide
4332.

The suitable cross-section of sewers to carry combined flow, is

A. circular
B. egg shaped
C. rectangular
D. horse shoe shaped.
Answer» C. rectangular
4333.

Hazin's formula is used for the settlement velocity of the particles of diameter

A. less than 0.01 mm
B. less than 0.05 mm
C. less than 0.1 mm
D. greater than 0.1 mm.
Answer» E.
4334.

The minimum diameter of a sewer is kept

A. 10 cm
B. 15 cm
C. 20 cm
D. 25 cm
E. 30 cm.
Answer» C. 20 cm
4335.

The minimum diameter of sewer to be adopted is

A. 10 cm
B. 12.5 cm
C. 15 cm
D. 25 cm.
Answer» D. 25 cm.
4336.

The intensity of rain is expressed in

A. cm/minute
B. cm/hour
C. cm/day
D. none of these.
Answer» C. cm/day
4337.

1000 kg of sewage contains

A. 0.112 kg in suspension
B. 0.112 kg in solution
C. 0.225 kg in solution
D. 0.450 kg in suspension
E. both (a) and (c) of above.
Answer» F.
4338.

The rational formula for peak drainage discharge, was evolved by

A. Fruhling
B. Lloyd David
C. Kuichling
D. All of these.
Answer» E.
4339.

The sewage treatment in septic tanks is due to

A. anaerobic decomposition
B. aerobic decomposition
C. parasitic decomposition
D. none of these.
Answer» B. aerobic decomposition
4340.

Which one of the following resists hydrogen sulphide corrosion

A. R.C.C.
B. Glazed stone wares
C. Asbestos cement
D. Glazed ware.
Answer» E.
4341.

Hume steel pipes are

A. steel pipes
B. R.C.C. pipes
C. steel shell coated from inside with cement mortar
D. steel shell coated from outside with cement mortar
E. both (c) and (d).
Answer» F.
4342.

Assertion (A) : The determination of pH value of sewerage is important. Reason (R) : The efficiency of certain treatment methods depends upon the availability of pH value.

A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not a correct explanation of A
C. A is true but R is false
D. A is false but R is true.
Answer» B. Both A and R are true but R is not a correct explanation of A
4343.

With self cleansing velocity in sewers

A. silting occurs at bottom
B. scouring occurs at bottom
C. both silting and scouring occur at bottom
D. neither silting nor scouring occurs at bottom.
Answer» E.
4344.

If the diameter of a sewer is 100 mm, the gradient required for generating self cleansing velocity, is

A. 1 in 60
B. 1 in 100
C. 1 in 120
D. none of these.
Answer» B. 1 in 100
4345.

To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by pottassium dichromate in the presence of

A. Hydrochloric acid
B. Sulphuric acid
C. Nitric acid
D. Citric acid.
Answer» C. Nitric acid
4346.

The grit and silt of the grit chambers, may not be used for

A. raising low lying areas by dumping
B. concreting
C. both (a) and (b)
D. neither (a) nor (b).
Answer» C. both (a) and (b)
4347.

In a sludge tank, the gas mainly produced, is

A. Oxygen
B. Nitrogen
C. Hydrogen
D. Carbon dioxide
E. Methane.
Answer» F.
4348.

Pick up the incorrect statement from the following for allowing workers to enter sewers

A. The particular manhole and one manhole on up stream and one manhole on down stream should remain open for 30 minutes
B. Proper tests for the presence of poisonous gases must be carried out
C. The men entering the manhole should be advised to smoke in the sewer
D. Warning signals should be erected
E. None of these.
Answer» D. Warning signals should be erected
4349.

The discharge per unit plan area of a sedimentation tank, is generally called

A. over flow rate
B. surface loading
C. over flow velocity
D. all the above.
Answer» E.
4350.

In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is

A. <img src="/_files/images/civil-engineering/waste-water-engineering/190-9.166-1.png">
B. <img src="/_files/images/civil-engineering/waste-water-engineering/190-9.166-2.png">
C. <img src="/_files/images/civil-engineering/waste-water-engineering/190-9.166-3.png">
D. <img src="/_files/images/civil-engineering/waste-water-engineering/190-9.166-4.png">
Answer» E.