The slope of sewer shall be__________________?
A. Given in the direction of natural slope of ground
B. Given in the direction opposite to natural slope of ground
C. Zero
D. Steeper than 1 in 20
The design discharge for the combined sewer system shall be taken as________________?
A. Equal to rainfall
B. Rainfall + dwf
C. Rainfall + 2 dwf
D. Rainfall + 6 dwf
The main disadvantage of cement concrete sewers is________________?
A. Less strength
B. Difficulty in construction
C. Difficulty in transportation due to heavy weight
D. Less life
An egg shaped section of sewer________________?
A. Is economical than circular section
B. Provides self cleansing velocity at low discharges
C. Is more stable than circular section
D. Is easy to construct
The most commonly used sewer under culverts is_______________?
A. Circular brick sewer
B. Circular cast iron sewer
C. Semi-elliptical sewer
D. Horse-shoe type sewer
The characteristics of fresh and septic sewage respectively are____________________?
A. Acidic and alkaline
B. Alkaline and acidic
C. Both acidic
D. Both alkaline
Which of the following retards the self purification of stream ?
A. Higher temperature
B. Sunlight
C. Satisfying oxygen demand
D. None of the above
Settling velocity increases with_______________?
A. Specific gravity of solid particles
B. Size of particles
C. Depth of tank
D. Temperature of liquid