500 Best Irrigation Engineering MCQ
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:
Q85). Plain sedimentation is a process of retaining water in a basin so that the suspended particles settles down as a result of the
a).Action of sun rays
b).Action of gravity and forces
c).Action of velocity of the particles
d).None of these
Correct Answer:
Action of gravity and forces
Explanation:
Q86). The rate of settling of a particle in water depends upon the
a).Viscosity of water
b).Density of water
c).Specific gravity of particle
d).All of these
Correct Answer:
All of these
Explanation:
Q87). The detention time for an ordinary plain sedimentation tank is
a).1 to 2 hours
b).2 to 4 hours
c).6 to 8 hours
d).20 to 24 hours
Correct Answer:
6 to 8 hours
Explanation:
Q88). In a plain sedimentation tank, under normal conditions, impurities are removed upto
a).0.5
b).0.6
c).0.7
d).0.8
Correct Answer:
0.7
Explanation: