civil engineering MCQs – Page 219

Practise multiple-choice questions from civil engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

civil engineering Mcqs

4361. The type of sewer which is suitable for both combined and separate system is_____________?
0

A. circular sewer

B. horse-shoe type sewer

C. egg shaped sewer

D. semi-elliptical sewer

4362. The working conditions in imhoff tanks are_______________?
0

A. aerobic in lower compartment and anaerobic in upper compartment

B. aerobic only

C. anaerobic in lower compartment and aerobic in upper compartment

D. anaerobic only

4363. Most of the bacteria in sewage are______________?
0

A. saprophytic

B. parasitic

C. anaerobic

D. pathogenic

4364. As compared to higher pH values, the contact period required for efficient chlorination at lower pH values is___________________?
0

A. smaller

B. same

C. none of the above

D. larger

4365. Ground water is usually free from________________?
0

A. suspended impurities

B. dissolved impurities

C. both suspended and dissolved impurities

D. none of the above

4366. If the total hardness of water is greater than its total alkalinity, the carbonate hardness will be equal to________________?
0

A. total hardness total alkalinity

B. total alkalinity

C. total hardness

D. non carbonate hardness

4367. Generally the detention period for grit chambers is kept as_______________?
0

A. 12 hours

B. 2-4 hours

C. 1 minute

D. 5 minutes

4368. Alum as a coagulant is found to be most effective when pH range of water is______________?
0

A. 2 to 4

B. 8 to 10

C. 4 to 6

D. 6 to 8

4369. The pathogens can be killed by_______________?
0

A. chlorination

B. none of the above

C. nitrification

D. oxidation

4370. The ratio of 5 day BOD to ultimate BOD is about_______________?
0

A. 3-Jan

B. 4-Mar

C. 1

D. 2/3

4371. Corrosion in concrete sewers is caused by______________?
0

A. dissolved oxygen

B. chlorine

C. nitrogen

D. septic conditions

4372. Which of the following compounds is widely used for algae control ?
0

A. sodium sulphate

B. copper sulphate

C. sodium chloride

D. calcium chloride

4373. The maximum discharge of a tube-well is about_________________?
0

A. 50 litres/sec

B. 500 litres/sec

C. 1000 litres/see

D. 5 litres/sec

4374. Facultative bacteria are able to work in________________?
0

A. presence of oxygen only

B. absence of oxygen only

C. presence of water

D. presence as well as in absence of oxygen

4375. Assertion A: Slow sand filters are more efficient in removal of bacteria than rapid sand filters. Reason R : The sand used in slow sand filters is finer than that in rapid sand filters. Select your answer based on the coding system given below?
0

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 the correct explanation of A

C. A is true but R is false

D. A is false but R is true

4376. The design discharge for the combined sewer system shall be taken as________________?
0

A. rainfall + 2 DWF

B. rainfall + 6 DWF

C. equal to rainfall

D. rainfall + DWF

4377. Percentage of bacterial load that can be removed from water by the process of plain sedimentation is about_______________?
0

A. 100

B. 75

C. 10 to 25

D. 50

4378. The hydraulic mean depth (HMD. for an egg-shaped sewer flowing two-third full is_______________?
0

A. none of the above

B. less than HMD when flowing full

C. greater than HMD when flowing full

D. equal to HMD when flowing full

4379. The disinfection efficiency of chlorine increases by_______________?
0

A. decreasing the time of contact

B. decreasing the temperature of water

C. increasing the temperature of water</strong>

D. correct answer is ?

E. only (1)

F. both (1) and (2)

4380. The most common cause of acidity in water is_______________?
0

A. nitrogen

B. oxygen

C. carbon dioxide

D. hydrogen

Previous Next

Showing 4361 to 4380 of 6149 mcqs