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This section includes 292 Mcqs, each offering curated multiple-choice questions to sharpen your Applied Chemistry knowledge and support exam preparation. Choose a topic below to get started.
1. |
In areas where light rains are uniformly distributed throughout the year, the type of seweragesystem to be adopted is |
A. | Separate system |
B. | Combined system |
C. | Partially combined system |
D. | None of these |
Answer» C. Partially combined system | |
2. |
Pick up the incorrect statement from the following. Intake of water supply should |
A. | Be nearer to the treatment plant |
B. | Receive water from purer zone of the source |
C. | Be located downstream of waste water disposal point |
D. | Remain easily accessible during floods |
Answer» D. Remain easily accessible during floods | |
3. |
To maintain aerobic biological activity, the moisture content of the compost mass should beabout |
A. | 45 % |
B. | 50 % |
C. | 55 % |
D. | 60 % |
Answer» D. 60 % | |
4. |
In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for adischarge Q, is |
A. | Q/(B × D) |
B. | Q/(L × D) |
C. | Q/L |
D. | Q/(B × L) |
Answer» E. | |
5. |
The fire demand for a city of 50,000 populations, according to Godrich formula, is |
A. | 40 mld |
B. | 42 mld |
C. | 44 mld |
D. | 48 mld |
Answer» D. 48 mld | |
6. |
Anti syphonage pipe is fitted |
A. | At the end of septic tanks (B) (C) (D) |
B. | On manholes |
C. | With a W.C. trap |
D. | At the beginning of sewer line |
Answer» D. At the beginning of sewer line | |
7. |
The sewage treatment units in which anaerobic decomposition of organic matter is used, arecalled |
A. | Imhoff tanks |
B. | Trickling filters |
C. | Sludge sedimentation tanks |
D. | None of these |
Answer» C. Sludge sedimentation tanks | |
8. |
The depth of the water table at a place is 45 m below the general ground level. To lift waterfrom a deep tube well in such a locality, the type of pump to be installed is |
A. | Centrifugal pump |
B. | Reciprocating pump |
C. | Deep well turbine pump |
D. | None of these |
Answer» D. None of these | |
9. |
If V is total consumption of water in litres for a population of N individuals, per capitaconsumption or water allowance for the water supply Q, is given by |
A. | Q = V/12N |
B. | Q = V/24N |
C. | Q = V/265N |
D. | None of these |
Answer» D. None of these | |
10. |
To prevent settling down of sewage both at the bottom and on the sides of a large sewer,selfcleaning 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 |
Answer» E. | |
11. |
The moisture content of sludge is reduced from 90% to 80% in a sludge digestion tank. Thepercentage decrease in the volume of sludge, is |
A. | 25 % (B) (C) (D) |
B. | 50 % |
C. | 10 % |
D. | 5 % |
Answer» C. 10 % | |
12. |
If D is the diameter of a circular sewer and D' is the top horizontal diameter of an equivalent eggshaped 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 |
Answer» D. D' = 0.94 D | |
13. |
If the flame of a miner's safety lamp in the upper layers of the sewer forms an explosive, thesewer certainly contains |
A. | Hydrogen sulphide |
B. | Carbon dioxide |
C. | Methane |
D. | Oxygen |
Answer» D. Oxygen | |
14. |
The formula which accepts the value of rugosity coefficient n = 0.012 to be used in Manning'sformula, is given by |
A. | Bazin |
B. | Crimp and Bruges |
C. | William-Hazen |
D. | Kutter |
Answer» C. William-Hazen | |
15. |
Water may not contain much impurity if its source is |
A. | Reservoirs |
B. | Stream flowing in plains |
C. | Lakes in lower regions |
D. | Spring along hill slopes |
Answer» E. | |
16. |
Standard unit of turbidity of water is in one litre of distilled water, one milligram of finelydivided |
A. | Silica |
B. | Mud |
C. | Clay |
D. | Organic matter |
Answer» B. Mud | |
17. |
Runoff is the quantity of water which flows |
A. | In sewer pipes |
B. | Due to leakage in pipes |
C. | In rivers |
D. | None of these |
Answer» D. None of these | |
18. |
The detention time of a circular tank of diameter d and water depth H, for receiving the sewageQ per hour, is |
A. | d² (0.011d + 0.785H)/Q |
B. | d (0.022d + 0.085H)/Q |
C. | d (0.785d + 0.011H)/Q |
D. | d (0.285d + 0.011H)/Q |
Answer» B. d (0.022d + 0.085H)/Q | |
19. |
If four fires break out in a city of population 40 lakhs and if each hydrant has three streams andduration of each fire is four hours, the total quantity of water required, is |
A. | 1880 kilo litres |
B. | 2880 kilo litres |
C. | 3880 kilo litres |
D. | 4880 kilo litres |
Answer» C. 3880 kilo litres | |
20. |
A pressure conduit laid underground, may not be subjected to |
A. | Internal pressure of water |
B. | Pressure due to external load |
C. | Longitudinal temperature stress |
D. | Longitudinal stresses due to unbalanced pressure to bends |
Answer» D. Longitudinal stresses due to unbalanced pressure to bends | |
21. |
Pathogens (or pathogenic bacteria’s) in water may cause |
A. | Typhoid |
B. | Cholera |
C. | Dysentery |
D. | All the above |
Answer» E. | |
22. |
For drains up to 15 cumecs, the depth “d” and “B” width are related by |
A. | d = 0.2 |
B. | d = 0.5 B |
C. | B = 0.2 d |
D. | B = 0.5 d |
Answer» C. B = 0.2 d | |
23. |
Assertion (A): The determination of pH value of sewerage is important. Reason (R): The efficiency of certain treatment methods depends upon the availability of pH value. |
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 |
Answer» B. Both A and R are true but R is not a correct explanation of A | |
24. |
The arrangement made for passing the sewer line below an obstruction below the hydraulicgradient lines called |
A. | Inverted syphon |
B. | Depressed sewer |
C. | Sag pipe |
D. | all of these |
Answer» E. | |
25. |
The intake opening is generally covered by a screen to prevent entry of debris etc. and its levelis kept |
A. | At the level of water of the source |
B. | At the bottom of water of the source |
C. | At about 2.5 m above the bottom |
D. | None of these |
Answer» D. None of these | |
26. |
Pick up the in-correct statement from the following: |
A. | Manholes are provided in sewer pipes at suitable intervals |
B. | Catch basins are generally provided in sewers for carrying drainage discharge |
C. | Inlets are generally provided in all sewers |
D. | None of these |
Answer» D. None of these | |
27. |
The most commonly used chemical for de-chlorination of water, is |
A. | Sodium thiosulphate |
B. | Sodium bisulphate |
C. | Sodium sulphite |
D. | Sulphur-dioxide |
Answer» D. Sulphur-dioxide | |
28. |
If G is the specific gravity of particles of diameter d, the velocity of settlement V in still water atT°C, according to Stoke's law, is |
A. | V = 418 (G - 1) d² [(3T + 70)/100] |
B. | V = 418 (G - 1) d [(3T - 70)/100] |
C. | V = 418 (G - 1) d² [(2T + 70)/100] |
D. | V = 418 (G - 1) d 4 [(3T + 70)/100] |
Answer» B. V = 418 (G - 1) d [(3T - 70)/100] | |
29. |
In detritus tanks |
A. | Flow velocity is kept 0.09 m/ |
B. | Detention period is kept 3 to 4 minutes |
C. | Organic and inorganic materials are separated |
D. | All the above |
Answer» E. | |
30. |
The duration of contact of chlorine with water before it is served to the first consumer, shouldbe at least |
A. | 10 to 15 minutes |
B. | 15 to 20 minutes |
C. | 20 to 30 minutes |
D. | 30 to 40 minutes |
Answer» D. 30 to 40 minutes | |
31. |
When gravity and pumping systems of water distribution are adopted, the type of distributionreservoir, is |
A. | Elevated tank |
B. | Ground source reservoir |
C. | Intz tank |
D. | Stand pipe |
Answer» B. Ground source reservoir | |
32. |
If the flame of a miner's safety lamp in a manhole extinguishes within 5 minutes, the sewercertainly contains |
A. | Hydrogen sulphide |
B. | Carbon dioxide |
C. | Methane |
D. | Oxygen |
Answer» C. Methane | |
33. |
The settling velocity of the particles larger than 0.06 mm in a settling tank of depth 2.4 is 0.33 mper sec. The detention period recommended for the tank, is |
A. | 30 minutes |
B. | 1 hour |
C. | 1 hour and 30 minutes |
D. | 2 hours |
Answer» E. | |
34. |
The U.C. (uniformity coefficient) D60/D10 for the best filter media sand should be |
A. | 2 |
B. | 3 |
C. | 4 |
D. | 5 |
Answer» B. 3 | |
35. |
Perched aquifers are generally found |
A. | On the surface of the ground |
B. | Below the surface of the ground but above water table |
C. | Below the water table |
D. | All the above |
Answer» C. Below the water table | |
36. |
If d is the diameter of the pipe, p is the total internal pressure, f is the permissible tensile stressand n is the effective of the joint, the thickness t of metal pipe, is |
A. | n (pd/2f) |
B. | (1/n) (pd/2f) |
C. | (1/n) (pd/3f) |
D. | (1/n) (pf/d) |
Answer» C. (1/n) (pd/3f) | |
37. |
The spacing of man holes along a straight portion of a sewer is 300 m, the diameter of the sewermay be |
A. | 0.9 cm |
B. | 1.2 m |
C. | 1.5 m |
D. | > 1.5 m |
Answer» E. | |
38. |
In areas where rainy season is limited to a few months, the type of sewerage systemrecommended is |
A. | Combined system |
B. | Partially separate system |
C. | Separate system |
D. | None of these |
Answer» D. None of these | |
39. |
When the reduced level of the water source is higher than the reduced level of the consumer'splace, water is generally supplied |
A. | By pumping system |
B. | By gravitational system |
C. | Both (a) and (b) |
D. | All the above |
Answer» C. Both (a) and (b) | |
40. |
The dilution ratio at which the odour is hardly detectable is generally called threshold odournumber and for public supplies it should not exceed |
A. | 3 |
B. | 5 |
C. | 7 |
D. | 9 |
Answer» B. 5 | |
41. |
Which of the following pumps in used to pump sewage solids with liquid sewage withoutclogging the pump is? |
A. | Centrifugal pump |
B. | Pneumatic ejector |
C. | Reciprocating pump |
D. | None of these |
Answer» B. Pneumatic ejector | |
42. |
Generally, first portion of a logistic curve for the population growth of a developing city,represents the growth of |
A. | Increasing |
B. | Decreasing |
C. | Constant |
D. | All the above |
Answer» B. Decreasing | |
43. |
The ratio of the diameter of a circular section and the side of a square section hydraulicallyequivalent, is |
A. | 1.095 |
B. | 1.085 |
C. | 1.075 |
D. | 1.065 |
Answer» B. 1.085 | |
44. |
The average domestic consumption under normal conditions in an Indian city per day perperson, is |
A. | 105 litres |
B. | 115 litres |
C. | 125 litres |
D. | 135 litres |
Answer» E. | |
45. |
The formula HL = n²V²L/R4/3 for the head loss in conduits is generally known as |
A. | Hazen-William's formula |
B. | Manning's formula |
C. | Darcy-Weisbach formula |
D. | Nikuradse formula |
Answer» C. Darcy-Weisbach formula | |
46. |
If p is total internal pressure, d is diameter of pressure conduit and t is thickness of conduit, theHoop's stress is |
A. | 𝜋𝑑𝑝/𝑡 |
B. | 𝜋𝑑𝑝/2𝑡 |
C. | dp/2t |
D. | dt/2p |
Answer» D. dt/2p | |
47. |
For the COD test of sewage, organic matter is oxidised by K2 Cr2O7 in the presence of |
A. | H2SO4 |
B. | HNO3 |
C. | HCl |
D. | None of these |
Answer» B. HNO3 | |
48. |
Hazen's formula VS = 418 (GS - Gw)d [(3T + 70)/100] is used for the settlement velocity of theparticles of diameter |
A. | Less than 0.01 mm |
B. | Less than 0.05 mm |
C. | Less than 0.1 mm |
D. | Greater than 0.1 mm |
Answer» E. | |
49. |
If P is population of a city in thousands and Q is fire demand in litres per minute, for properestimate of water, the Empirical formula Q = 1135 [(P/5) + 10] is suggested by |
A. | National Board of fire under-writers |
B. | Freeman |
C. | Kuichling |
D. | None of these |
Answer» C. Kuichling | |
50. |
If the side of a square sewer is 1000 mm, the diameter of a hydraulically equivalent circularsection, is |
A. | 1045 mm |
B. | 1065 mm |
C. | 1075 mm |
D. | 1095 mm |
Answer» E. | |