500 Best Environmental Engineering- MCQ
Q77). The bacteria which can survive without oxygen is called
a).Anaerobic bacteria
b).Pathogenic bacteria
c).Aerobic bacteria
d).Non pathogenic bacteria
Correct Answer:
Anaerobic bacteria
Explanation:
Q78). Bacteria which cause disease are called
a).Anaerobic bacterias
b).Facultative bacterias
c).Aerobic bacterias
d).None of these
Correct Answer:
None of these
Explanation:
Q79). The total count of bacteria per cubic centimetre for domestic purposes varies from
a).0 to 100
b).100 to 150
c).150 to 200
d).200 to 250
Correct Answer:
0 to 100
Explanation:
Q80). Copper sulphate is the most common chemical used for controlling
a).Bacteria
b).Algae
c).Silt
d).Mineral matter
Correct Answer:
Algae
Explanation:
Q81). Bio chemical oxygen demand (BOD) of safe drinking water must be
a).0
b).10
c).50
d).100
Correct Answer:
0
Explanation:
Q82). The method adopted for removing bushes, branches, debris etc from water is known as
a).Sedimentation
b).Coagulation
c).Screening
d).Filteration
Correct Answer:
Screening
Explanation:
Q83). In the process of screening, the screens should be inclined at an angle of
a).10° to 20°
b).30° to 40°
c).45° to 60°
d).70° to 85°
Correct Answer:
45° to 60°
Explanation:
Q84). The area of the openings in screens should be such that the velocity of flow through them does not exceed
a).0.75 to 1 m/s
b).1.5 to 3 m/s
c).3 to 5 m/s
d).5 to 6 m/s
Correct Answer:
0.75 to 1 m/s
Explanation: