A. A particle to travel along its length
B. A particle to travel from top surface to bottom sludge zone
C. The flow of sewage to fill the tank
D. None of these
Related Mcqs:
- The settling velocity of the particles larger than 0.06 mm in a settling tank of depth 2.4 is 0.33 m per sec. The detention period recommended for the tank, is____________________?
A. 30 minutes
B. 1 hour
C. 1 hour and 30 minutes
D. 2 hours - The width of a settling tank with 2 hour detention period for treating sewage 378 cu m per hour, is __________________?
A. 5 m
B. 5.5 m
C. 6.5 m
D. 7 m - The dimensions of a rectangular settling tank are: length 24 m, width 6 m and depth 3 m. If 2 hour detention period for tanks is recommended, the rate of flow of sewage per hour, is_____________________?
A. 204 cu.m
B. 208 cu.m
C. 212 cu.m
D. 216 cu.m - In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is____________________?
A. Q/(B × D)
B. Q/(L × D)
C. Q/L
D. Q/(B × L) - The detention time of a circular tank of diameter d and water depth H, for receiving the sewage Q per hour, is________________?
A. d² (0.011d + 0.785H)/Q
B. d (0.022d + 0.085H)/Q
C. d (0.785d + 0.011H)/Q
D. d (0.285d + 0.011H)/Q - For a grit chamber, if the recommended velocity of flow is 0.2 m/sec and detention period is 2 minutes, the length of the tank, is__________________?
A. 16 m
B. 20 m
C. 24 m
D. 30 m - The grit and silt of the grit chambers, may not be used for_________________?
A. Raising low lying areas by dumping
B. Concreting
C. Both A. and B.
D. Neither A. nor B - The settling velocity of a spherical particle of diameter less than 0.1 mm as per Stock’s law, is__________________?
A. Vs = 418 (Gs – Gw) d [(3T + 70)/100]
B. Vs = 418 (Gs – Gw)d² [(3T + 70)/100]
C. Vs = 218 (Gs – Gw)d² [(3T + 70)/100]
D. Vs = 218 (Gs – Gw)d [(3T + 70)/100] - To prevent settling down of sewage both at the bottom and on the sides of a large sewer, self-cleaning velocity recommended for Indian conditions, is_________________?
A. 0.50 m/sec
B. 0.60 m/sec
C. 0.70 m/sec
D. 0.75 m/sec - The recommended detention period for grit chambers is_______________?
A. 1 minute
B. 2 minutes
C. 3 minutes
D. 5 minutes
