Q.1) The suitable method of forecasting population for a young and rapidly increasing city is :
A) Arithmetical increase method
B) Geometrical increase method
C) Incremental increase method
D) Graphical method
Option (B)
Q.2) The amount of residual chlorine left in public water supply for safety against pathogenic bacteria is about :
A) 0.01 – 0.05 ppm
B) 0.05 – 0.5 ppm
C) 0.5 – 1.0 ppm
D) 1.0 – 5.0 ppm
Option (B)
Q.3) The velocity of flow of water in a sedimentation tank is about :
A) 5 – 10 cm/s
B) 15 – 30 cm/s
C) 15 – 30 cm/min
D) 15 – 30 cm/hr
Option (C)
Q.4) Alum as a coagulant is found to be most effective when the pH range of water is :
A) 2 – 4
B) 4 – 6
C) 6 – 8
D) 8 – 10
Option (C)
Q.5) The effective size of sand particles used in slow sand filters is :
A) 0.25 – 0.35 mm
B) 0.35 – 0.60 mm
C) 0.60 – 1.00 mm
D) 1.00 – 1.80 mm
Option (A)
Q.6) Disinfection of water results in :
A) Removal of turbidity
B) Removal of hardness
C) Killing of disease bacteria
D) Complete sterilisation
Option (C)
Q.7) The treatment of water with bleaching powder is known as :
A) Prechlorination
B) Superchlorination
C) Dechlorination
D) Hypochlorination
Option (D)
Q.8) The major disadvantage of lime soda process of water softening is that :
A) It is unsuitable for turbid and acidic water
B) Huge amount of precipitate is formed which creates a disposal problem
C) The effluent cannot be reduced to zero hardness
D) It is unsuitable for softening the water of excessive hardness
Option (B)
Q.9) Which of the following compound is widely used for algae control?
A) Sodium sulphate
B) Copper sulphate
C) Sodium chloride
D) Calcium chloride
Option (B)
Q.10) The type of valve which is provided to control the flow of water in the distribution system at street corners and where the pipelines intersect is :
A) Check valve
B) Sluice valve
C) Safety valve
D) Scour valve
Option (B)
Q.11) Sewerage system is usually designed for :
A) 10 years
B) 25 years
C) 50 years
D) 75 years
Option (B)
Q.12) Most suitable section of sewer in separate sewage system is :
A) Rectangular section
B) Circular section
C) Standard form of egg-shaped sewer
D) Modified egg-shaped section
Option (B)
Q.13) Dissolved oxygen in streams is :
A) Maximum at noon
B) Minimum at noon
C) Maximum at midnight
D) Same throughout the day
Option (A)
Q.14) Which of the following unit works in anaerobic conditions?
A) Sludge digestion tank
B) Sedimentation tank
C) Activated sludge treatment
D) Trickling filters
Option (A)
Q.15) The maximum efficiency of BOD removal is achieved in :
A) Oxidation pond
B) Oxidation ditch
C) Aerated lagoons
D) Trickling filters
Option (B)
Q.16) The gas from the sludge digestion tank is mainly composed of :
A) Nitrogen
B) Carbon dioxide
C) Hydrogen sulphide
D) Methane
Option (D)
Q.17) The biochemical treatment of sewage effluents is essentially a process of :
A) Oxidation
B) Dehydration
C) Reduction
D) Alkalinization
Option (A)
Q.18) Incrustation of the tubewell pipes may result in :
A) Discharge of highly corrosive acidic water
B) Discharge of highly alkaline water
C) Reduced discharge from tube well
D) Excessive discharge of sand with water
Option (C)
Q.19) The primary pollutant caused by incomplete combustion of organic matter is :
A) Ozone
B) Carbon monoxide
C) Sulphur dioxide
D) None of the above
Option (B)
Q.20) Blue baby disease (methemoglobinemia) in children is caused by the presence of excess :
A) Chlorides
B) Nitrates
C) Fluorides
D) Lead
Option (B)
