You are asked to design sewer pipes of diameters 0.4 m to 0.9 m at maximum flow, you will assume the sewer flow running at___________________?

Related Mcqs:

1. If the discharge of a sewer running half is 628 1.p.s., i = 0.001, and n = 0.010, the diameter of the sewer, is__________________?

   A. 1.39 m
   B. 1.49 m
   C. 1.59 m
   D. 1.69 m

2. 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

3. The angle subtended by the surface of sewer water with partial flow, at sewer centre is 120°, the depth of sewerage is________________________?

   A. 20 cm
   B. 25 cm
   C. 40 cm
   D. 50 cm

4. Assertion A.: The minimum self cleansing velocity in the sewer, at least once a day, must be generated. Reason (R): If certain deposition takes place and is not removed, it obstructs free flow and causes further deposition leading to complete blocking of the sewer?

   A. Both A and R are true and R is the correct explanation of A
   B. Both A and R are true but R is not a correct explanation of A
   C. A is true but R is false
   D. A is false but R is true

5. In Chezy’s formula V = C rs for calculating the velocity of flow in circular sewer of diameter running full, the value of hydraulic mean radius is_______________?

   A. D
   B. D /2
   C. D/3
   D. D/4

6. For sewer mains of 0.5 to 1 m diameter, the ratio of maximum daily sewage flow to the average daily sewage flow is assumed__________________?

   A. 1.5
   B. 2.0
   C. 2.5
   D. 3.0

7. ¾th or ¼th extra space is left in sewer pipes at maximum discharge for_________________?

   A. Low estimates of the average and maximum flows
   B. Large scale infiltration of storm water
   C. Unexpected increase in population
   D. All the above

8. Sewer pipes are designed for maximum discharge with 25% to 33% vacant cross-sectional area for__________________?

   A. Unexpected large scale infiltration of stream water
   B. Unexpected increase in the population
   C. Under estimates of maximum and average flows
   D. All of the above

9. If the flame of a miner’s safety lamp in the upper layers of the sewer forms an explosive, the sewer certainly contains_______________?

   A. Hydrogen sulphide
   B. Carbon dioxide
   C. Methane
   D. Oxygen

10. The spacing of man holes along a straight portion of a sewer is 300 m, the diameter of the sewer may be__________________?

    A. 0.9 cm
    B. 1.2 m
    C. 1.5 m
    D. > 1.5 m