A. 2 to 3 mm
B. 3 to 5 mm
C. 5 to 8 mm
D. 8 to 10 mm
Related Mcqs:
- The spacing of bars for perforations in coarse screens used for the treatment of sewage, is ____________________?
A. 20 mm
B. 30 mm
C. 40 mm
D. 50 mm - The use of coarse screens for the disposal of sewage, may be dispensed with by______________?
A. Comminutor
B. Shredder
C. Both A. and B.
D. Neither A. nor B. - Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is ?
A. Centrifugal pump
B. Pneumatic ejector
C. Reciprocating pump
D. None of these - The ratio of maximum sewage flow to average sewage flow for mains up to 1 m in diameter, is___________________?
A. 1.5
B. 2.0
C. 3.0
D. 4.0 - The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is_____________________?
A. 0.05552 cumec
B. 0.05554 cumec
C. 0.05556 cumec
D. 0.0556 cumec - A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is____________________?
A. 100
B. 1000
C. 5000
D. 10000 - The ratio of maximum sewage flow to average sewage flow for trunk mains having diameters more than 1.25 m, is____________________?
A. 1.5
B. 2.0
C. 3.0
D. 4.0 - If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is_________________?
A. 50 mg/l
B. 100 mg/l
C. 150 mg/l
D. 250 mg/l - If 2% solution of a sewage sample is incubated for 5 days at 20°C and depletion of oxygen was found to be 5 ppm, B.O.D. of the sewage is____________________?
A. 200 ppm
B. 225 ppm
C. 250 ppm
D. None of these - If q is the average sewage flow from a city of population P, the maximum sewage flow______________?
A. Q = [(4 + )/(18 + )] q
B. Q = [(18 + P)/(4 + )] q
C. Q = [(18 + )/(4 + )] q
D. Q = [(5 + )/((15 + )] q
