A. 100 mm dia.
B. 150 mm dia.
C. 225 mm dia.
D. All of these
Related Mcqs:
- 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 - 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 - For trunk sewers more than 1.25 m in diameter, the ratio of the maximum daily sewage flow to the average daily sewage flow is assumed________________?
A. 1.5
B. 2.0
C. 2.5
D. 3.0 - If the diameter of sewer is 225 mm, the gradient required for generating self cleansing velocity, is___________________?
A. 1 in 60
B. 1 in 100
C. 1 in 120
D. None of these - 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 gradient of sewers depends upon_________________?
A. Velocity of flow
B. Diameter of the sewer
C. Discharge
D. All the above - In circular sewers if depth of flow is 0.2 times the full depth, the nominal gradient,______________?
A. Is only provided
B. Is doubled
C. Is trebled
D. Is not enough - If the diameter of a sewer is 150 mm, the gradient required for generating self cleansing velocity, is________________?
A. 1 in 60
B. 1 in 100
C. 1 in 120
D. None of these - For design of sewers, percentage of sewage discharge is assumed_____________________?
A. 65 to 70%
B. 70 to 75%
C. 75 to 80%
D. 85% - If the depletion of oxygen is found to be 5 ppm after incubating a 2.5% solution of sewage sample for 5 days at 21°C, B.O.D. of the sewage is_____________________?
A. 50 ppm
B. 100 ppm
C. 150 ppm
D. 200 ppm
