If the diameter of a sewer is 100 mm, the gradient required for generating self cleansing velocity is__________________?

Related Mcqs:

1. 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

2. 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

3. 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

4. Self-cleansing velocity is__________________?

   A. Velocity at dry weather flow
   B. Velocity of water at flushing
   C. Velocity at which no accumulation remains in the drains
   D. Velocity of water in a pressure filter

5. 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

6. The self-cleansing velocity of water flowing through pipe lines, is___________________ ?

   A. 2 metres/sec
   B. 1 metre/sec
   C. 0.5 metre/sec
   D. 0.25 metre/sec

7. With self cleansing velocity in sewers___________________?

   A. Silting occurs at bottom
   B. Scouring occurs at bottom
   C. Both silting and scouring occur at bottom
   D. Neither silting nor scouring occurs at bottom

8. 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

9. 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

10. If D is the diameter of a circular sewer and D’ is the top horizontal diameter of an equivalent egg shaped section, the relationship which holds good, is_______________?

    A. D’ = 0.64 D
    B. D’ = 0.74 D
    C. D’ = 0.84 D
    D. D’ = 0.94 D