Explore topic-wise MCQs in Civil Engineering.

This section includes 641 Mcqs, each offering curated multiple-choice questions to sharpen your Civil Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

If is the diameter of a circular sewer and is the top horizontal diameter of an equivalent egg shaped section, the relationship which holds good, is

A. = 0.64
B. = 0.74
C. = 0.84
D. = 0.94
E. .
Answer» D. = 0.94
2.

The detention time () of a settling tank, may be defined as the time required for

A. a particle to travel along its length
B. a particle to travel from top surface to bottom sludge zone
C. the flow of sewage to fill the tank
D. none of these.
Answer» D. none of these.
3.

If is the diameter of upper circular portion, the overall depth of New Egg shaped sewer section, is

A. 1.250
B. 1.350
C. 1.425
D. 1.625
E. .
Answer» E. .
4.

For estimating the peak run off the rational formula = 0.0278 KpA was evolved by

A. Kinchling
B. Lloyd Davis
C. Frubling
D. all the above.
Answer» E.
5.

If the depth of flow in a circular sewer is 1/4th of its diameter , the wetted perimeter is

A. π
B. .
Answer» D.
6.

The Chezy's constant in the formula = 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.
7.

For the open drain ( = 0.025) shown in the below figure, the discharge is

A. 26.88 cumecs
B. 27.88 cumecs
C. 28.88 cumecs
D. 29.88 cumecs.
Answer» D. 29.88 cumecs.
8.

5 days-biochemical oxygen demand (BOD) is taken at a temperature of

A. 0°C
B. 15°C
C. 20°C
D. 25°C.
Answer» D. 25°C.
9.

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
10.

For a circular sewer of diameter running partially full with central angle α,

A. all the above.
Answer» F.
11.

The drainage area of a town is 12 hectares. Its 40% area is hard pavement ( = 0.85), the 40% area is unpaved streets ( = 0.20) and the remaining is wooded areas ( = 0.15). Assuming the time of concentration for the areas as 30 minutes and using the formula the maximum run off is

A. 0.10 cumec
B. 0.12 cumec
C. 0.15 cumec
D. 0.20 cumec.
Answer» D. 0.20 cumec.
12.

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

A. none of these.
Answer» B.
13.

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.
14.

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.
15.

If is the rugosity coefficient, is the hydraulic depth, 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
16.

For drains up to 15 cumecs, the depth and width are related by

A. = 0.2
B. = 0.5
C. = 0.2
D. =
E. .
Answer» C. = 0.2
17.

If the discharge of a sewer running half is 628 1.p.s., = 0.001, and = 0.010, the diameter of the sewer, is

A. 1.39 m
B. 1.49 m
C. 1.59 m
D. 1.69 m
E. 1.79 m.
Answer» E. 1.79 m.
18.

The formula used for determining flow velocities in sewers, is known as

A. Chezy's formula
B. Bazin's formula
C. Kutter's formula
D. Manning's formula.
Answer» E.
19.

The formula which accepts the value of rugosity coefficient = 0.012 to be used in Manning's formula, is given by

A. Bazin
B. Crimp and Bruge
C. William-Hazen
D. Kutter.
Answer» C. William-Hazen
20.

The value of Chezy's constant is used in

A. Chezy's formula
B. Bazin's formula
C. Kutter's
D. Manning's formula.
Answer» D. Manning's formula.
21.

For the COD test of sewage, organic matter is oxidised by KCr0 in the presence of

A. H
B. SO
C. HNO
D. HCl
E. none of these.
Answer» B. SO
22.

If is the diameter of upper circular portion, the overall depth of a standard egg shaped section, is

A. 1.25
B. 1.5
C. 1.75
D. 2
E. .
Answer» D. 2
23.

Which one of the following gases is most significant as air pollutant ?

A. Carbondioxide
B. Oxygen
C. Nitrogen
D. Sulphur-dioxide
Answer» E.
24.

Which one of the following part of human body withstands minimum radiation ?

A. Thyroid
B. Kidneys
C. Eyes
D. Ovaries/testis
Answer» E.
25.

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.
26.

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.
27.

Which one of the following tests is used for testing sewer pipes ?

A. Water test
B. Ball test
C. Mirror test
D. All of these
Answer» E.
28.

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.
29.

You are asked to design sewer pipes of diameters 0.4 m to 0.9 m at maximum flow, you will assume the sewer flow running at___________________?

A. Full depth
B. Half full
C. Two third full
D. Three fourth full
Answer» C. Two third full
30.

Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is ?

A. Centrifugal pump
B. Pneumatic ejector
C. Reciprocating pump
D. None of these
Answer» B. Pneumatic ejector
31.

When drainage to sewage ratio is 20, the peak dry weather flow is_______________?

A. 20% of the design discharge
B. Slightly less than 5% of the design discharge
C. Slightly more than 5% of the design discharge
D. None of these
Answer» C. Slightly more than 5% of the design discharge
32.

weight of water, the hydraulic mean depth of the sewer and the bed slope w is the unit of the sewer, then the tractive force exerted by flowing water, is________________________?

A. w r S S
B. w r1/2
C. w r S
D. w r2/3
Answer» B. w r1/2
33.

Water content of sewage is about___________________?

A. 90 %
B. 95 %
C. 99 %
D. 9.9 %
Answer» E.
34.

Ventilating shafts are provided to a sewer line at every__________________?

A. 100 m
B. 150 m
C. 200 m
D. 300 m
Answer» E.
35.

Traps_________________?

A. Are water seals which prevent the entry of foul gases
B. Are used to trap the rats entering sewers
C. Dissolve the foul gases
D. Create symphonic action to increase the quick disposal of sewerage
Answer» B. Are used to trap the rats entering sewers
36.

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

A. Hydrochloric acid
B. Sulphuric acid
C. Nitric acid
D. Citric acid
Answer» C. Nitric acid
37.

To prevent settling down of sewage both at the bottom and on the sides of a large sewer, self-cleaning velocity recommended for Indian conditions, is_________________?

A. 0.50 m/sec
B. 0.60 m/sec
C. 0.70 m/sec
D. 0.75 m/sec
Answer» E.
38.

To maintain aerobic biological activity, the moisture content of the compost mass should be about_________________?

A. 45 %
B. 50 %
C. 55 %
D. 60 %
Answer» D. 60 %
39.

The width of a settling tank with 2 hour detention period for treating sewage 378 cu m per hour, is __________________?

A. 5 m
B. 5.5 m
C. 6.5 m
D. 7 m
Answer» E.
40.

The width of a rectangular sewer is twice its depth while discharging 1.5 m/sec. The width of the sewer is______________?

A. 0.68 m
B. 0.88 m
C. 1.36 m
D. 1.76 m
Answer» D. 1.76 m
41.

The water carried sewerage system removes__________________?

A. Domestic sewage
B. Industrial sewage
C. Storm sewage
D. All the above
Answer» E.
42.

The value of Chezy’s constant C = 157.6/(1.81 + K/ ) is used in__________________?

A. Chezy’s formula
B. Bazin’s formula
C. Kutter’s formula
D. Manning’s formula
Answer» C. Kutter’s formula
43.

The use of coarse screens for the disposal of sewage, may be dispensed with by______________?

A. Comminutor
B. Shredder
C. Both A. and B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
44.

The underground sewers are more subjected to________________?

A. Tensile force
B. Compressive force
C. Bending force
D. Shearing force
Answer» C. Bending force
45.

The temperature affects the________________?

A. Biological activity of bacteria in sewage
B. Solubility of gases in sewage
C. Viscosity of sewage
D. All the above
Answer» E.
46.

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
47.

The stone ware sewers_________________?

A. Are used for carrying sewage and drainage from houses
B. Are manufactured from clays and shale
C. After casting are dried and burnt at temperature 150°C, 700°C and 1200°C
D. All the above
Answer» E.
48.

The standard B.O.D. of water is taken for_________________?

A. 1 day
B. 2 days
C. 3 days
D. 5 days
Answer» E.
49.

The spacing of man holes along a straight portion of a sewer is 300 m, the diameter of the sewer may be__________________?

A. 0.9 cm
B. 1.2 m
C. 1.5 m
D. > 1.5 m
Answer» E.
50.

The spacing of bars for perforations in coarse screens used for the treatment of sewage, is ____________________?

A. 20 mm
B. 30 mm
C. 40 mm
D. 50 mm
Answer» E.