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.

451.

A sewer running partially full and hurried with back filled, fails in compression due to

A. weight of the pipe
B. weight of the back fill
C. superimposed traffic loads
D. all the above.
Answer» E.
452.

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

A. 1.250 D
B. 1.350 D
C. 1.425 D
D. 1.625 D.
Answer» E.
453.

The angle subtended by the surface of sewer water with partial flow, at sewer centre is 120°, the depth of sewerage is

A. 20 cm
B. 25 cm
C. 40 cm
D. 50 cm
Answer» E.
454.

For a grit chamber, if the recommended velocity of flow is 0.2 m/sec and detention period is 2 minutes, the length of the tank, is

A. 16 m
B. 20 m
C. 24 m
D. 30 m.
Answer» D. 30 m.
455.

The average temperature of sewage in India, is

A. 10°C
B. 15°C
C. 20°C
D. 25°C
Answer» D. 25¬∞C
456.

The most widely used pump for lifting sewage is

A. centrifugal pump
B. reciprocating pump
C. pneumatic ejector
D. air pressure pump.
Answer» B. reciprocating pump
457.

The drainage area of a town is 12 hectares. Its 40% area is hard pavement (K = 0.85), the 40% area is unpaved streets (K = 0.20) and the remaining is wooded areas (K = 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.
458.

For providing an Indian type W.C., the R.C.C. slabs in the toilet portion

A. should be sunk by 20 cm
B. should be kept 20 cm above the adjacent portion
C. should be sunk by 50 cm
D. need not be sunk.
Answer» D. need not be sunk.
459.

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.
460.

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.
461.

The normal values of over flow rates for secondary sedimentation tanks, ranges between

A. 25, 000 to 35, 000 litres/sqm/day
B. 40, 000 to 50, 000 litres/sqm/day
C. 50, 000 to 60, 000 litres/sqm/day
D. 80, 000 to 10, 000 litres/sqm/day
Answer» B. 40, 000 to 50, 000 litres/sqm/day
462.

In case of sewer lines

A. water test is carried out to check water tightness of the joints
B. test for straightness is carried out with the help of a lamp and mirror
C. obstruction test is carried out with the. help of smooth ball of diameter 13 mm
D. all the above.
Answer» E.
463.

The sludge does not contain waste water from

A. bath rooms
B. wash basins
C. kitchen sinks
D. toilets.
Answer» E.
464.

The standard B.O.D. of water is taken for

A. 1 day
B. 2 days
C. 3 days
D. 5 days
Answer» E.
465.

The asbestos cement sewers are

A. light in weight
B. not structurally strong to bear large compressive stress
C. susceptible to corrosion by sulphuric acid
D. All the above.
Answer» E.
466.

If the pH value of sewage is 7

A. it is acidic
B. it is alkaline
C. it is neutral
D. none of these.
Answer» D. none of these.
467.

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).
468.

Pathogens (or pathogentic bacterias) in water may cause

A. typhoid
B. cholera
C. dysentery
D. infectious hepatitis
Answer» E.
469.

It is customary to design a sewer for D.W.F. on the basis of

A. average demand
B. twice the average demand
C. thrice the average demand
D. four times the average demand.
Answer» D. four times the average demand.
470.

If the flame of a miner's safety lamp in the upper layers of the sewer forms an explosive, the sewer certainly contains

A. Hydrogen sulphide
B. Carbon dioxide
C. Methane
D. Oxygen
Answer» D. Oxygen
471.

The arrangement made for passing the sewer line below an obstruction below the hydraulic gradient lines called

A. inverted syphon
B. depressed sewer
C. sag pipe
D. all of these.
Answer» E.
472.

The sewer which transports the sewage to the point of treatment, is called

A. house sewer
B. out-fall sewer
C. branch sewer
D. lateral
Answer» C. branch sewer
473.

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.
474.

Stoneware sewers are available in size

A. 10 cm
B. 15 cm
C. 20 cm
D. 25 cm
Answer» E.
475.

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
476.

The sewerage system consists of

A. house sewer
B. lateral sewer
C. branch sewer
D. main sewer
Answer» E.
477.

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
478.

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

A. 1.39 m
B. 1.49 m
C. 1.59 m
D. 1.69 m
Answer» E.
479.

The effluent of a septic tank is

A. fit for discharge into any open drain
B. foul and contains dissolved and suspended solids
C. as good as that from a complete treatment
D. none of these.
Answer» B. foul and contains dissolved and suspended solids
480.

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

A. thyroid
B. kidneys
C. eyes
D. ovaries/testis.
Answer» E.
481.

The detention time (t) 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.
482.

The sewer which resists sulphide corrosion, is

A. Brick sewer
B. Cast iron sewer
C. R.C.C. sewer
D. Lead sewer
Answer» E.
483.

The pH value of sewage is determined with the help of

A. Imhoff Cone
B. turbidimeter
C. potentiometer
D. none of these.
Answer» D. none of these.
484.

The pressure exerted by

A. the sewage when running full from inside, is called internal pressure
B. the internal pressure if any, causes tensile stress in the pipe material
C. pressure sewers are designed to be safe in tension
D. All the above.
Answer» E.
485.

For efficient working of a sewer, it must be ensured that

A. minimum velocity of 0.45 m/sec, is maintained at its minimum flow
B. a maximum velocity of 0.90 m/sec, is maintained at its maximum flow
C. both (a) and (b)
D. neither (a) nor (b).
Answer» D. neither (a) nor (b).
486.

Hydraulic mean radius is

A. mean radius of sewer
B. difference in heads between two points in circular pipes
C. mean of radii in a pipe line of varying cross-sections
D. cross-sectional area/wetted perimeter.
Answer» E.
487.

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 m
D. 6.5 m
Answer» E.
488.

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
489.

Water content of sewage is about

A. 0.9
B. 0.95
C. 0.99
D. 9.9%.
Answer» E.
490.

In detritus tanks,

A. flow velocity is kept 0.09 m/sec
B. detention period is kept 3 to 4 minutes
C. organic and inorganic materials are separated
D. all the above.
Answer» E.
491.

The disintegrating pump in which solid matter is broken up before passing out, is

A. centrifugal pump
B. reciprocating pump
C. pneumatic ejector
D. none of these.
Answer» B. reciprocating pump
492.

The sewer which collects the discharge from a collecting system and delivers it to a treatment plant, is known

A. house sewer
B. lateral sewer
C. branch sewer
D. sewer outfall.
Answer» E.
493.

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
Answer» D. 0.0556 cumec
494.

If the depletion of oxygen is found to be 5 ppm after incubating a 2.5% solution of sewage sample for 5 days at 21°C, B.O.D. of the sewage is

A. 50 ppm
B. 100 ppm
C. 150 ppm
D. 200 ppm
Answer» E.
495.

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.
496.

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.
497.

The normal values of over flow rates for sedimentation tanks using coagulent, ranges between

A. 25, 000 to 35, 000 litres/sqm/day
B. 40, 000 to 50, 000 litres/sqm/day
C. 50, 000 to 60, 000 litres/sqm/day
D. 80, 000 to 100, 000 litres/sqm/day
Answer» D. 80, 000 to 100, 000 litres/sqm/day
498.

The reduced levels of the string at the consecutive sight rails A and B are 203.575 m, 203.475 m respectively. If the difference of their R.D.s is 10 m, the gradient of the sewer line is

A. 1 in 100 upward
B. 1 in 500 upward
C. 1 in 100 downward
D. 1 in 503 upward.
Answer» D. 1 in 503 upward.
499.

The amount of oxygen consumed by the aerobic bacterias which cause the aerobic biological decomposition of sewage, is known

A. Bio-Chemical Oxygen Demand (B.O.D.)
B. Dissolved Oxygen (D.O.)
C. Chemical Oxygen Demand (C.O.D.)
D. None of these.
Answer» C. Chemical Oxygen Demand (C.O.D.)
500.

Imhoff cone is used to determine

A. settlable solids
B. suspended solids
C. dissolved solids
D. none of these.
Answer» B. suspended solids