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.

251.

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

A. Potassium permanganate
B. Sulphuric acid and napthamine
C. Phenol-di -sulphuric acid potassium hydroxide
D. None of these
Answer» C. Phenol-di -sulphuric acid potassium hydroxide
Discussion
252.

For detecting the nitrates in sewage, the colour may be developed by adding________________?

A. Potassium permanganate
B. Sulphuric acid and napthamine
C. Phenol-di -sulphuric acid and potassium hydroxide
D. None of these
Answer» D. None of these
Discussion
253.

For design purposes, the normal rate of infiltration of ground water into the sewer, is___________________?

A. 500 litres/km/cm
B. 1000 litres/km/cm
C. 1500 litres/km/cm
D. 2000 litres/km/cm
Answer» E.
Discussion
254.

For design of sewers, percentage of sewage discharge is assumed_____________________?

A. 65 to 70%
B. 70 to 75%
C. 75 to 80%
D. 85%
Answer» D. 85%
Discussion
255.

For a peak discharge of 0.0157 cumec, with a velocity of 0.9 m/sec, the diameter of the sewer main, is________________?

A. 10 cm
B. 12 cm
C. 15 cm
D. 18 cm
Answer» D. 18 cm
Discussion
256.

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
Discussion
257.

For a continuous flow type of sedimentation tanks__________________?

A. Width of the tank is normally kept about 6 m
B. Length of the tank is normally kept 4 to 5 times the width
C. Maximum horizontal flow velocity is limited to 0.3 m/minute
D. All the above
Answer» E.
Discussion
258.

Flocculated particles do not change their___________________?

A. Size
B. Shape
C. Weight
D. None of these
Answer» E.
Discussion
259.

Facultative bacteria survive in_____________________?

A. The presence of oxygen
B. The absence of oxygen
C. Both cases A. and B.
D. Neither A. nor B.
Answer» D. Neither A. nor B.
Discussion
260.

During purification process of sewage the gas given off, is________________?

A. Carbon dioxide
B. Hydrogen
C. Ammonia
D. All the above
Answer» E.
Discussion
261.

Dry weather flow is__________________?

A. Average daily rate of flow
B. Average monthly rate of flow
C. Average annual rate of flow
D. Water supply allowance per capital
Answer» E.
Discussion
262.

Dry water flow in a combined sewer, is______________________?

A. Industrial sewage
B. Domestic sewage
C. Storm water
D. Inclusive of domestic and industrial sewage but excludes storm water
Answer» D. Inclusive of domestic and industrial sewage but excludes storm water
Discussion
263.

Drop manholes at the junctions of sewer lines, are provided if________________?

A. Invert level of a branch sewer is more than 60 cm that of the main sewer
B. Sewer line runs along a main road
C. Ordinary manhole cannot be built
D. Two sewer lines intersect
Answer» B. Sewer line runs along a main road
Discussion
264.

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.
Discussion
265.

Dried sewage after treatment is used as____________________?

A. Fertilizer
B. Building material
C. Chemical for lowering B.O.D.
D. Base material for paints
Answer» B. Building material
Discussion
266.

Disposal to sewage in large cities, is done in__________________?

A. Irrigation
B. Dilution
C. Oxidation
D. Purification
Answer» C. Oxidation
Discussion
267.

Discrete or granular particles change their_________________ ?

A. Size
B. Shape
C. Weight
D. None of these
Answer» E.
Discussion
268.

Dilution method of disposing of sewage, is not preferred to_______________?

A. When sewage is fresh
B. When diluting water has high dissolved oxygen content
C. When diluting water is used for water supply near the point of sewage disposed
D. When the diluting water is having flow currents
Answer» D. When the diluting water is having flow currents
Discussion
269.

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.
Discussion
270.

Depletion of ozone layer in the outer atmosphere may cause___________________ ?

A. Lung cancer
B. Skin cancer
C. Bronchitis
D. Heart disorder
Answer» C. Bronchitis
Discussion
271.

‘Cowl’ is provided at___________________?

A. Lower end of ventilating column
B. Upper end of ventilating column
C. Upper end of the manhole
D. First step in manhole
Answer» C. Upper end of the manhole
Discussion
272.

Clogging of sewers, is caused due to_______________?

A. Silting
B. Low discharge
C. Greasy and oily matters
D. All the above
Answer» E.
Discussion
273.

Chlorination of water is done for the removal of____________________?

A. Bacterias
B. Suspended solids
C. Sediments
D. Hardness
Answer» B. Suspended solids
Discussion
274.

Cement concrete sewers are only suitable if non-scouring velocity is between_________________?

A. 2.5 to 3.0 m/sec
B. 3.0 to 4.0 m/sec
C. 3.5 to 4.5 m/sec
D. 4.5 to 5.5 m/sec
Answer» B. 3.0 to 4.0 m/sec
Discussion
275.

Boussinesq’s equation for ascertaining unit pressure at a depth on sewers due to traffic loads, is__________________?

A. pt = 3H3p/2 Z5
B. pt = 2H3p/3 Z5
C. pt = 3H3p/2Z5
D. pt = 2 3p/3Z5
Answer» B. pt = 2H3p/3 Z5
Discussion
276.

Bottom openings 15 cm × 15 cm in the standing baffle wall are provided________________?

A. 15 cm c/c
B. 22.5 cm c/c
C. 30 cm c/c
D. 50 cm c/c
Answer» C. 30 cm c/c
Discussion
277.

Bio-chemical oxygen demand (BOD) for the first 20 days in generally referred to_______________?

A. Initial demand
B. First stage demand
C. Carbonaceous demand
D. All of these
Answer» E.
Discussion
278.

Before discharging the foul sewage into rivers, it is generally treated by_____________________?

A. Screening
B. Sedimentation
C. Oxidation
D. All the above
Answer» E.
Discussion
279.

At the junction of sewers___________________?

A. Top of smaller sewer is kept lower
B. Top of larger sewer is kept lower
C. Tops of both the sewers are at the same level
D. None of these
Answer» E.
Discussion
280.

Assertion A.: The minimum self cleansing velocity in the sewer, at least once a day, must be generated. Reason (R): If certain deposition takes place and is not removed, it obstructs free flow and causes further deposition leading to complete blocking of the sewer?

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
Discussion
281.

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
Discussion
282.

Assertion A. : Discharging the effluents from the oxidation ponds just up stream of lakes or reservoirs is undesirable. Reason (R) : The discharged algae get settled in the reservoirs and cause anaerobic decomposition and other water qualities_________________?

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
Discussion
283.

Assertion A.: A free board of 0.3 m is provided above the top sewage line in septic tanks. Reason (R): It helps to accommodate the scum in the septic tank_________________?

A. Both A and R is true and R is the correct explanation of A
B. Both A and R is 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 is true but R is not a correct explanation of A
Discussion
284.

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
Discussion
285.

are available in size Stoneware sewers________________?

A. 10 cm
B. 15 cm
C. 20 cm
D. All the above
Answer» E.
Discussion
286.

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
Discussion
287.

An inverted siphon is designed generally for____________________?

A. One pipe
B. Two pipes
C. Three pipes
D. Four pipes
Answer» D. Four pipes
Discussion
288.

Aerobic bacterias___________________?

A. Flourish in the presence of free oxygen
B. Consume organic matter as their food
C. Oxidise organic matter in sewage
D. All the above
Answer» E.
Discussion
289.

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
Discussion
290.

Acid regression stage of sludge digestion at a temperature 21°C extends over a period of______________?

A. 15 days
B. 30 days
C. 60 days
D. 90 days
Answer» E.
Discussion
291.

A well oxidized sewage contains nitrogen mainly as___________________?

A. Nitrates
B. Nitrites
C. Free ammonia
D. None of these
Answer» B. Nitrites
Discussion
292.

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.
Discussion
293.

A sewer pipe contains 1 mm sand particles of specific gravity 2.65 and 5 mm organic particles of specific gravity 1.2, the minimum velocity required for removing the sewerage, is_____________________?

A. 0.30 m/sec
B. 0.35 m/sec
C. 0.40 m/sec
D. 0.45 m/sec
Answer» E.
Discussion
294.

A safety lamp when inserted in the upper portion of a manhole causes flames. It indicates the presence of______________?

A. Carbondioxide gas
B. Hydrogen sulphide gas
C. Methane gas
D. Petrol vapours
Answer» D. Petrol vapours
Discussion
295.

A rainfall may be classified as acidic if its pH value is less or equal to________________?

A. 6
B. 7
C. 5
D. 6.5
Answer» D. 6.5
Discussion
296.

A rain sanitary sewer is constructed to carry_________________ ?

A. Sanitary sewage
B. Storm sewage
C. Surface water
D. Ground water
Answer» B. Storm sewage
Discussion
297.

A nuisance is experienced in diluting water if dilution factor is less than_________________?

A. 100
B. 60
C. 40
D. 20
Answer» E.
Discussion
298.

A manhole is generally provided at each__________________?

A. Bend
B. Junction
C. Change of gradient
D. All the above
Answer» E.
Discussion
299.

A manhole is classified as shallow if its depth is between_________________?

A. 0.4 to 0.5 m
B. 0.5 to 0.7 m
C. 0.7 to 0.9 m
D. 0.9 to 1.20 m
Answer» D. 0.9 to 1.20 m
Discussion
300.

A five 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.
Discussion