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
Related Mcqs:
- 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 - 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 - If the diameter of a sewer is 100 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 - 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 - 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 - 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 - In sewers designed with self cleansing velocity________________?
A. The bottom is silted
B. The bottom is scoured
C. Both silting and scouring occur at the bottom
D. Neither silting nor scouring occurs at the bottom - The sewers___________________?
A. Must be of adequate size to avoid over flow
B. Must flow under gravity ½ to ¾ full
C. Must be laid at least 2 to 3 m deep to collect /water from the basements
D. All the above - At the junction of sewers___________________?
A. Top of smaller sewer is kept lower
B. Top of larger sewer is kept lower
C. Tops of both the sewers are at the same level
D. None of these - 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
