Q.1) The removal of dissolved organic matter occurs in –
A) Slow sand filters
B) Trickling filters
C) Rapid sand filters
D) Dual media filters
Option (A)
Q.2) A Galvanised Iron (G.I.) pipe has a coating of –
A) Zinc
B) Lead
C) Silver
D) Aluminium
Option (A)
Q.3) The presence of ozone in water is indicated by –
A) Red colour
B) Light yellow colour
C) Blue colour
D) Black colour
Option (B)
Q.4) The process used for the removal of dissolved carbon dioxide from the supply water is –
A) Coagulation
B) Agitation
C) Aeration
D) Sedimentation
Option (C)
Q.5) Disinfection of water is done by –
A) Filteration
B) Passing chlorine
C) Ozone
D) Alum
Option (B)
Q.6) Alum increases –
A) Hardness of water
B) Carbonates in water
C) Sulphates in water
D) Acidity in water
Option (D)
Q.7) The slow sand filter should be cleaned if the loss of head becomes more than –
A) 0.75 m
B) 1.2 m
C) 2.2 m
D) 3.5 m
Option (B)
Q.8) The period of cleaning for rapid sand filter is –
A) 2 – 3 months
B) 24 – 48 months
C) 24 – 48 hours
D) 24 – 48 weeks
Option (C)
Q.9) Coagulants are used when turbidity of water is more than –
A) 50 ppm
B) 60 ppm
C) 70 ppm
D) 80 ppm
Option (A)
Q.10) The path of a particle in sedimentation tank is –
A) Parabolic
B) Straight
C) Elliptical
D) Circular
Option (A)
Q.11) A chemical used to inhibit the growth of algae is –
A) Chlorine
B) Iodine
C) Lead
D) Algicides
Option (D)
Q.12) Disease caused by protozoal infections is –
A) Poliomyelitis
B) Amoebic dysentery
C) Bacillary dysentery
D) Malaria
Option (B)
Q.13) Lead poisoning occurs when the lead content in water exceeds –
A) 0.05 ppm
B) 0.1 ppm
C) 0.15 ppm
D) 0.5 ppm
Option (D)
Q.14) The permissible limit of nitrate content in potable water is –
A) 25 ppm
B) 45 ppm
C) 100 ppm
D) 150 ppm
Option (B)
Option (A)
Q.16) The compensation for losses, theft and wastage of water, an allowance provided is –
A) 5%
B) 10%
C) 15%
D) 25%
Option (C)
Q.17) The sub-surface water obtained under pressure is generally known as –
A) Open well
B) Tube well
C) Infiltration well
D) Artesian well
Option (D)
Q.18) The specific retention is least in –
A) Coarse gravel
B) Sand
C) Clay
D) Silt
Option (A)
Q.19) The most widely used tube well in India is –
A) Strainer well
B) Cavity well
C) Slotted well
D) Perforated well
Option (A)
Q.20) The coefficient of uniformity for slow sand filters is –
A) 1.35
B) 1.55
C) 1.75
D) 2.05
Option (C)