1. In dry feeding type of coagulants, the dose of coagulant is controlled by
Correct : B. worm wheel
2. The open wells or dug wells are also known as
Correct : D. all of these
3. The maximum permissible quantity of lead in water for domestic supplies is
Correct : B. 0.05 ppm
4. The ideal method of disinfection of swimming pool water is by
Correct : C. ozonisation
5. A pipe sunk into the ground to tap the underground water is called
Correct : B. tube well
6. The method adopted for removing, bushes branches, debries etc. from water is known as
Correct : C. screening
7. The water carriage sewage system removes
Correct : D. all of these
8. Colloidal impurities if associated with organic matter having bacterias becomes the chief source of
Correct : B. epidemic
9. The quantity of storm water (Q) in liter per second is given by Q = CA3/4. This formula is called
Correct : C. Dicken's formula
10. The leakage of sewage from the sewer into the soil surrounding the water is called ex-filtration.
Correct : A. Agree
11. Which of the following statement is correct?
Correct : D. all of the above
12. The percentage ratio of the oxygen available in sewage to the oxygen required to satisfy one stage of bio-chemical oxygen demand (B.O.D.) is termed as
Correct : C. relative stability
13. The continuous flow of water may be expected from
Correct : B. artesian springs
14. The void spaces in the filtering material act like a
Correct : C. tiny settling basins
15. Residual chlorine in water is determined by
Correct : B. starch-iodide
16. Rpid sand filters are suitable for small towns and villages.
Correct : B. No
17. The prsence of sodium chloride in water
Correct : B. softens the water
18. A scour valve, in a water distribution system, is provided at
Correct : A. low points
19. The growth of population may be conveniently represented by
Correct : B. logistic curve
20. The earth's water circulatory system is known as.
Correct : B. hydrological cycle
21. The odour of water can be determined by
Correct : B. Osmoscope
22. Grit should be removed from sewage before
Correct : D. all of the above
23. When a pervious strata is sandwitched between two impervious strata of cup shape, the well is called a tube well.
Correct : B. False
24. If the level of source of water is higher than that of the place of consumption, the system adopted for supplying water is