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This section includes 140 Mcqs, each offering curated multiple-choice questions to sharpen your Waste Water Engineering knowledge and support exam preparation. Choose a topic below to get started.
1. |
Which of the following is formed from oxidation of organic matter in the presence of oxygen? |
A. | NO₃ |
B. | SO₄ |
C. | H₂S |
D. | NH₂ |
Answer» B. SO₄ | |
2. |
______ zone lies between Euphotic and Benthic zone. |
A. | Euphotic zone |
B. | Benthic zone |
C. | Littoral zone |
D. | Climate zone |
Answer» D. Climate zone | |
3. |
What is the value of BOD of industrial sewage in kg/day, given population equivalent as 6000 persons? |
A. | 480 |
B. | 160 |
C. | 270 |
D. | 100 |
Answer» B. 160 | |
4. |
Which one of the following lakes has minimum productivity? |
A. | Mesotrophic lake |
B. | Senescent lake |
C. | Oligotrophic lake |
D. | Eutrophic lake |
Answer» D. Eutrophic lake | |
5. |
________ is the process of acceleration of eutrophication due to increased phosphorous content in lakes. |
A. | Photosynthesis |
B. | Chemical eutrophication |
C. | Cultural eutrophication |
D. | Custom eutrophication |
Answer» D. Custom eutrophication | |
6. |
_______ is the process of overgrowth of plants and algae in lakes. |
A. | Transpiration |
B. | Reproduction |
C. | Eutrophication |
D. | Photosynthesis |
Answer» D. Photosynthesis | |
7. |
The expression of relative stability at 37°C is given by ___________ |
A. | S = (1-(0.794)ᵀ³⁷) |
B. | S = 100 (1-(0.794)ᵀ³⁷) |
C. | S = 1-(0.794)ᵀ²⁰ |
D. | S = 100 (1-(0.630)ᵀ³⁷) |
Answer» E. | |
8. |
Which of the following process is used to remove the colloidal particles from the effluent? |
A. | Chemical precipitation |
B. | Chemical coagulation |
C. | Ion exchange |
D. | Adsorption |
Answer» C. Ion exchange | |
9. |
In which unit operation, gases are released or absorbed in the effluent? |
A. | Gas transfer |
B. | Ion transfer |
C. | Solute stabilization |
D. | Solids Transfer |
Answer» B. Ion transfer | |
10. |
Which of the following id the correct expression of population equivalent? |
A. | BOD of industrial sewage in kg/day * 0.08 |
B. | 0.08 * BOD of industrial sewage kg/day |
C. | BOD of industrial sewage kg/day / 0.08kg/person/day |
D. | BOD of industrial sewage kg/day + 0.08 |
Answer» D. BOD of industrial sewage kg/day + 0.08 | |
11. |
Solids are removed from the wastewater by which of the following unit operation? |
A. | Inter facial contact |
B. | Solid stabilization |
C. | Ion transfer |
D. | Solids transfer |
Answer» E. | |
12. |
The dimension formula of dynamic viscosity is ____________ |
A. | ML⁻¹T |
B. | ML⁻¹T⁻¹ |
C. | ML⁻²T⁻² |
D. | ML⁻¹T⁻³ |
Answer» C. ML⁻²T⁻² | |
13. |
The head loss through the screen is given by HL = k* (Vₜ² – Vₐ²), where Vₜ and Vₐ are velocities through and above the screen respectively. What is the value of constant k? |
A. | 1 |
B. | 0.0050 |
C. | 0.0729 |
D. | 0.0236 |
Answer» D. 0.0236 | |
14. |
The dilution factor is 400. What should be the type of treatment given to the water? |
A. | Preliminary treatment |
B. | Sedimentation, Flocculation |
C. | Complete treatment |
D. | No treatment |
Answer» B. Sedimentation, Flocculation | |
15. |
Organic contaminants are removed from the wastewater by ____________ |
A. | Water softening |
B. | Demineralization |
C. | Absorption |
D. | Adsorption |
Answer» E. | |
16. |
By which process, odor producing substances are oxidized? |
A. | Chlorination |
B. | Liming |
C. | Re-carbonation |
D. | Super-chlorination |
Answer» E. | |
17. |
The pollution zones in the river are divided into how many types? |
A. | 3 |
B. | 4 |
C. | 6 |
D. | 8 |
Answer» C. 6 | |
18. |
5 days BOD at 20°C is ___ of total demand. |
A. | 20% |
B. | 47% |
C. | 68% |
D. | 100% |
Answer» D. 100% | |
19. |
In which zone, decomposition of the dead organism takes place? |
A. | Climate zone |
B. | Benthic zone |
C. | Littoral zone |
D. | Euphotic zone |
Answer» C. Littoral zone | |
20. |
The minimum depth to which sewage should be discharged of sea water is ____________ |
A. | 0.5m |
B. | 1m |
C. | 2m |
D. | 3m |
Answer» E. | |
21. |
In which of the following, large impurities are attached with air bubbles to remove it from the wastewater? |
A. | Sludge digestion tank |
B. | Primary sedimentation |
C. | Vacuum floatation |
D. | Oxidation pond |
Answer» D. Oxidation pond | |
22. |
Calculate the percentage of relative stability, given 5 day incubation period at 37°C. |
A. | 50% |
B. | 60% |
C. | 90% |
D. | 99% |
Answer» D. 99% | |
23. |
The turbulence decreases the DO content of water. |
A. | True |
B. | False |
C. | May be True or False |
D. | Can't say |
Answer» C. May be True or False | |
24. |
Partially oxidized sewage contains __________ |
A. | Nitrites and Nitrates |
B. | Nitrates and sulfur |
C. | Sulfates and nitrates |
D. | Nitrites and sulfur |
Answer» E. | |
25. |
Which of the following expression is correct regarding deoxygenation constant where symbols have their usual meaning? |
A. | KDT = KD20 + (1.047)ᵀ⁻²⁰ |
B. | KDT = KD20 / (1.047)ᵀ⁻²⁰ |
C. | KDT = KD20 (1.047)ᵀ⁻²⁰ |
D. | KDT = KD20 (1.04ᵀ) |
Answer» D. KDT = KD20 (1.04ᵀ) | |
26. |
The maximum spacing between the bars in medium screen is ____________ |
A. | 40mm |
B. | 50mm |
C. | 70mm |
D. | 90mm |
Answer» B. 50mm | |
27. |
In which pollution zone of the river, water retains its original dissolved oxygen concentration? |
A. | Zone of degradation |
B. | Zone of recovery |
C. | Zone of active decomposition |
D. | Zone of clean water |
Answer» E. | |
28. |
The unit of dynamic viscosity is ____________ |
A. | Metre²/Sec |
B. | Metre/Sec |
C. | Pa * Sec |
D. | Dimensionless |
Answer» D. Dimensionless | |
29. |
Which of the following is a prime lake pollutant? |
A. | Iodine |
B. | Phosphorous |
C. | Potassium |
D. | Sodium |
Answer» C. Potassium | |
30. |
The tolerance limit of pH value of sewage to be discharged into sea water is ____________ |
A. | 1-5ppm |
B. | 2-9ppm |
C. | 5.5-9ppm |
D. | 6-10ppm |
Answer» D. 6-10ppm | |
31. |
Which type of pollution is Cultural eutrophication? |
A. | Water pollution |
B. | Noise pollution |
C. | Thermal pollution |
D. | Soil pollution |
Answer» B. Noise pollution | |
32. |
The tolerance limit of oil and grease of sewage to be disposed on land is ____________ |
A. | 40ppm |
B. | 30ppm |
C. | 20ppm |
D. | 10ppm |
Answer» C. 20ppm | |
33. |
The coefficient of drag for a transition settling is ____________ |
A. | CD = 18.5/R⁰·⁶ |
B. | CD = 24/R |
C. | CD = 8.5/R⁰·⁶ |
D. | CD = R/24 |
Answer» B. CD = 24/R | |
34. |
Screens are inclined to the direction of flow to ____________ |
A. | Increase the flow velocity |
B. | Increase the opening area |
C. | Decrease the flow velocity |
D. | Increase the head loss |
Answer» D. Increase the head loss | |
35. |
How many types of aerators are commonly used in the treatment of wastewater? |
A. | 2 |
B. | 3 |
C. | 4 |
D. | 5 |
Answer» D. 5 | |
36. |
In which pollution zone of the river, the dissolved oxygen reduced to 0? |
A. | Zone of degradation |
B. | Zone of recovery |
C. | Zone of clean water |
D. | Zone of active decomposition |
Answer» E. | |
37. |
The dilution factor is expressed by _____________ |
A. | Volume of diluted sample + Volume of sewage |
B. | Volume of diluted sample / Volume of sewage |
C. | Volume of diluted sample – Volume of sewage |
D. | Volume of diluted sample* Volume of sewage |
Answer» C. Volume of diluted sample – Volume of sewage | |
38. |
The aerobic decomposition of sulfurous organic matter gives __________ |
A. | Nitrites and water |
B. | Carbon dioxide and water |
C. | Sulfates and water |
D. | Nitrogen and Ammonia |
Answer» D. Nitrogen and Ammonia | |
39. |
Which chemical is used for the titration of waste water for finding its chloride content? |
A. | Potassium chloride |
B. | Sodium chloride |
C. | Potassium chromate |
D. | Potassium dichromate |
Answer» D. Potassium dichromate | |
40. |
The type of solids which floats in sewage is __________ |
A. | Suspended solids |
B. | Settleable solids |
C. | Dissolved solids |
D. | Total solids |
Answer» B. Settleable solids | |
41. |
The presence of which of the following in sewage indicates nitrogen content before decomposition of sewage? |
A. | Nitrites |
B. | Nitrates |
C. | Free ammonia |
D. | Albuminoid nitrogen |
Answer» E. | |
42. |
The presence of free ammonia in sewage represents ____________ |
A. | Air pollution |
B. | Old pollution |
C. | Recent pollution |
D. | Water pollution |
Answer» D. Water pollution | |
43. |
The presence of which of the following indicates old pollution? |
A. | Nitrates |
B. | Nitrites |
C. | H₂S |
D. | Sulfates |
Answer» E. | |
44. |
The odor quality of compound is ammoniacal. Identify the type of compound from the following options. |
A. | Acetic acid |
B. | Benzene |
C. | Ammonia |
D. | Methane |
Answer» D. Methane | |
45. |
The wastewater from the kitchen is an example of __________ |
A. | Black water |
B. | Yellow water |
C. | Green water |
D. | Grey water |
Answer» E. | |
46. |
The type of wastewater from the flushing operation of toilet is __________ |
A. | Green water |
B. | Red water |
C. | Black water |
D. | Brown water |
Answer» D. Brown water | |
47. |
The temperature of sewage increases. What will be the effect on the dissolved oxygen in sewage? |
A. | Remains constant |
B. | Increase |
C. | Decrease |
D. | No effect |
Answer» D. No effect | |
48. |
What is the minimum quantity of dissolved oxygen that should be present in the treated sewage? |
A. | 6ppm |
B. | 4ppm |
C. | 1ppm |
D. | 10ppm |
Answer» C. 1ppm | |
49. |
_______ indicates the freshness of sewage. |
A. | Turbidity |
B. | Color |
C. | Temperature |
D. | COD |
Answer» C. Temperature | |
50. |
Identify the incorrect statement from the following? |
A. | High odor intensity indicates odorless water |
B. | Fresh sewage is odorless |
C. | Turbidity can be measured by turbidity rod |
D. | NTU is a unit of turbidity |
Answer» B. Fresh sewage is odorless | |