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.
Options
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.
Correct Answer
Both A and R are true and R is the correct explanation of A
Waste Water Engineering problems
Search Results
1. In case of sewer lines
Options
A. water test is carried out to check water tightness of the joints
B. test for straightness is carried out with the help of a lamp and mirror
C. obstruction test is carried out with the. help of smooth ball of diameter 13 mm
Correct Answer: The gases produced in sludge digestion process, contain 75% carbon dioxide
6. 3.0 ml of raw sewage is diluted to 300 ml. The D.O. concentration of the diluted sample at the beginning of the test was 8 mg/l. After 5 day-incubation at 20°C, the DO. concentration was 5 mg/l. The BOD of raw sewerage is