Multiple choice question for engineering
Set 1
1. The process of burning of municipal solid waste at high temperature is called
a) Incineration
b) Composting
c) Land filing
d) Shredding
Answer
Answer: a [Reason:-] Incineration is the most sanitary method of disposal of municipal solid waste. Solid waste should have high calorific value.
2. Which of the following is a biodegradable waste?
a) Polythene bags
b) Synthetic fiber
c) Food waste
d) Paper
Answer
Answer: c [Reason:] Polythene bags, synthetic fiber and paper are non biodegradable wastes whereas food waste is a biodegradable waste.
3. In which method of disposal of municipal solid waste, the waste is dumped in the soil?
a) Incineration
b) Composting
c) Land filing
d) Shredding
Answer
Answer: c [Reason:] Land filling is a process of disposal of solid waste under the soil. It is usually done in low lying areas to prevent unhygienic conditions.
4. Which of the following is correct regarding disposal of waste by land filling?
a) Economical method
b) Preferred in low lying areas
c) Foul gases are not produced
d) Separation of different types of waste not required
Answer
Answer: c [Reason:] Land fill gases are produced during the dumping of waste. They are foul smell creating unhygienic conditions.
5. The density of ash produced in the municipal solid waste is
a) 100 kg/m3
b) 450 kg/m3
c) 700 kg/m3
d) 1000 kg/m3
Answer
Answer: c [Reason:] The range of the d density of ash produced from the municipal solid waste is 700-850kg/m3.
6. The process of decomposition of biodegradable solid waste by earthworms is called
a) Land fills
b) Shredding
c) Vermi-composting
d) Composting
Answer
Answer: c [Reason:] The process of decomposition of biodegradable solid waste by earthworms is called Vermi-composting.
7. The waste produced in cotton mills are
a) Municipal solid waste
b) Non biodegradable waste
c) Hazardous waste
d) Non hazardous waste
Answer
Answer: d [Reason:] The industrial waste is produced by cotton mills which are biodegradable and are non hazardous.
8. Which of the following is not the land filling method?
a) Bangalore method
b) Area method
c) Depression method
d) Trench method
Answer
Answer: a [Reason:] Bangalore method is a method of composting whereas area, depression and trench method are the land filling method.
9. ______ is a liquid that passes through solid waste and extract suspended impurities from it.
a) Leachate
b) Sludge
c) Distilled water
d) Municipal waste
Answer
Answer: a [Reason:] Leachate is a liquid that passes through solid waste and extract suspended impurities from it. It can be minimized by the use of clay lines.
10. Which of the following is not the municipal solid waste?
a) Radioactive substance
b) Ashes
c) Food waste
d) Rubbish
Answer
Answer: a [Reason:] Rubbish, food waste and food waste are municipal solid waste, whereas radioactive substances are industrial waste.
11. Which of the following waste can be decomposed by bacteria?
a) Radioactive substance
b) Ashes
c) Food waste
d) Rubbish
Answer
Answer: c [Reason:] Food waste can be decomposed by bacteria as they are biodegradable waste, whereas ashes, rubbish is non biodegradable.
12. ______ is the cutting and tearing of municipal solid waste.
a) Land fills
b) Shredding
c) Pulverization
d) Composting
Answer
Answer: b [Reason:] Shredding is the cutting and tearing of municipal solid waste. It helps in reducing the size and volume of municipal solid waste.
13. _________ is the crushing and grinding of municipal solid waste.
a) Land fills
b) Shredding
c) Pulverization
d) Composting
Answer
Answer: c [Reason:] Pulverization is the crushing and grinding of municipal solid waste. It changes the character of municipal solid waste and reduced its volume by 40%.
14. In which method of composting, decomposition of anaerobic waste takes place?
a) Indian method
b) Depression method
c) Bangalore method
d) Trench method
Answer
Answer: c [Reason:] In the Bangalore method of composting, decomposition of anaerobic waste takes place. It is better than Indore method.
15. Which of the following is a biological method of disposal of municipal solid waste?
a) Land fills
b) Shredding
c) Pulverization
d) Composting
Answer
Answer: d [Reason:] Composting is a biological method of decomposing the municipal solid waste under aerobic and anaerobic condition. It results in the production of humus.
Set 2
1. Which of the following is not a part of photochemical smog?
a) NO2
b) O3
c) PAN
d) SPM
Answer
Answer: d [Reason:] Photochemical smog includes NO2 , O3 and PAN. The damage to vegetation is caused by NO2, O3 and PAN.
2. Which air pollutant cause corrosion of building?
a) SO2
b) SO3
c) CO
d) NO2
Answer
Answer: a [Reason:] SO2 is a colorless and irritant gas that causes corrosion of building.
3. Which of the following air pollutant effects plants the most?
a) Fluorine
b) SO2
c) PAN
d) HCl
Answer
Answer: a [Reason:] Fluorine is the most dangerous air pollutant that affects plant, whereas SO2, PAN and HCl effects the leaf of the plant.
4. The size of cigarette particles is
a) 1μm
b) 10μm
c) <1μm d) >10μm
Answer
Answer: c [Reason:] Cigarette particles are <1μm and >25% particles are deposited in the lungs.
5. Concentration of fluorine that cause a phototoxicological effect on the plant is
a) 0.1μg/m3
b) 0.3μg/m3
c) 0.5μg/m3
d) 1μg/m3
Answer
Answer: b [Reason:] Fluorine is produced through aluminium or glass industries and it causes a phototoxicological effect on the plant at a concentration of 0.3μg/m3.
6. Which of the following gas is not colorless?
a) NO
b) O3
c) Pb
d) SO3
Answer
Answer: a [Reason:] NO is a highly reactive gas which is reddish brown in color, whereas O3, Pb and SO3 are colorless gas.
7. The effective height of stack is given by
a) Plume height / Actual height of the stack
b) Plume height * Actual height of the stack
c) Plume height – Actual height of the stack
d) Plume height + Actual height of the stack
Answer
Answer: d [Reason:] Effective height of the stack, H = h1 + h2 where, h1 is the plume height and h2 is the actual height of stack.
8. The chimney is emitting particulate matter. Which of the following is the correct expression of the height of the chimney? Here ‘Kp’ represents the emission of particulate matter.
a) HC = 74 Kp0.27
b) HC = 14 Kp0.27
c) HC = 14 Kp0.47
d) HC = 74 Kp0.33
Answer
Answer: a [Reason:] Height of the chimney HC = 74 Kp0.27 where HC is in metre and ‘Kp’ is in tonnes per hours.
9. What is the minimum height of the chimney in a thermal power plant of capacity 350MW?
a) 100m
b) 220m
c) 380m
d) 60m
Answer
Answer: b [Reason:] As the capacity of thermal plant lies between 200MW and 500MW, the minimum height height of the chimney is 220m.
10. Which of the following is the correct expression of the height of chimney emitting sulfur dioxide?
a) HC = 74 Kp0.27
b) HC = 14 Kp0.33
c) HC = 14 Kp0.47
d) HC = 74 Kp0.33
Answer
Answer: b [Reason:] Height of the chimney, HC = 14 Kp0.33 when the chimney is emitting sulfur dioxide. Here, the unit of ‘Kp’ is in kg/hour and HC is in metre.
Set 3
1. Which of the following is an anaerobic process for treating sewage?
a) Oxidation pond
b) Imhoff tank
c) Oxidation ditch
d) Rotating Biological Contactors
Answer
Answer: b [Reason:] Oxidation pond, Oxidation ditch and Rotating Biological Contactors are an aerobic process of treating sewage whereas Imhoff tank is an anaerobic process of treating sewage.
2. The minimum design depth of oxidation pond is
a) 0.3m
b) 0.5m
c) 1m
d) 1.5m
Answer
Answer: c [Reason:] The minimum design depth of oxidation pond is 1m while its maximum design depth is 1.5m.
3. State whether the following statement is true or false.
Oxidation pond is ineffective in removing pathogenic bacteria.
a) True
b) False
Answer
Answer: b [Reason:] Oxidation pond is highly efficient in removing pathogenic bacteria with an efficiency of 99.9%.
4. The detention period of oxidation pond is
a) 12-36 hours
b) 4 hours
c) 10-20 days
d) 30-60 seconds
Answer
Answer: c [Reason:] Oxidation ponds have a long detention period between 10 to 20 days.
5. The maximum BOD removal efficiency of an oxidation pond is
a) 90%
b) 68%
c) 70%
d) 80%
Answer
Answer: a [Reason:] The BOD removal efficiency of an oxidation pond lies between 80% and 90%, so the maximum BOD removal efficiency is 90%.
6. What is the minimum depth of water to be kept in oxidation pond?
a) 0.3m
b) 0.5m
c) 1m
d) 1.5m
Answer
Answer: c [Reason:] The minimum depth of water to be kept in oxidation pond is 0.3m and the depth of sludge deposited in the pond is 0.02m per year.
7. Which chemical is added to the oxidation pond to avoid bad odor?
a) Calcium chloride
b) Sodium nitrate
c) Potassium chloride
d) Silver nitrate
Answer
Answer: b [Reason:] Sodium nitrate is added to the oxidation pond to avoid bad odor. It acts as an oxidizing agent and also as the food of the plant.
Set 4
1. In which of the following filter, water is passed under higher pressure?
a) Slow sand filter
b) Rapid sand filter
c) Dual media filter
d) Pressure filter
Answer
Answer: d [Reason:] The pressure filter is a type of rapid sand filter kept in a closed container where water is passed under higher pressure.
2. What is the range of pressure in pressure filter?
a) 1-5 kg/cm2
b) 2-5 kg/cm2
c) 3-7 kg/cm2
d) 1-8 kg/cm2
Answer
Answer: c [Reason:] The range of pressure of pressure filter is 3-7 kg/cm2, which is done by pumping either in horizontal or vertical type pressure filter.
3. The diameter of the vertical type pressure filter is
a) 2-2.5 m
b) 1 m
c) 5 m
d) 10m
Answer
Answer: a [Reason:] The diameter of the vertical type pressure filter is 2-2.5 m and its length varies from 2.5 to 8m.
4. State whether the following statement is true of false.
Filtration operation in pressure filter is same as in rapid sand filter.
a) True
b) False
Answer
Answer: b [Reason:] In pressure filter, the coagulated water is applied to filter directly without any mixing or flocculation process, whereas in rapid sand filter, the flocculation takes place after coagulation and then it is applied to the filtration process.
5. The effective size of a pressure sand filter is ______
a) 0.45mm
b) 0.7mm
c) 0.8mm
d) 0.9mm
Answer
Answer: a [Reason:] The effective size of a pressure sand filter lies in the range of 0.35-0.6mm and its common value is 0.45mm.
6. What is the value of uniformity coefficient in a pressure sand filter?
a) 1
b) 1.5
c) 2
d) 2.5
Answer
Answer: b [Reason:] The value of uniformity coefficient in a pressure sand filter lies between 1.2 and 1.7 and its common value is 1.5.
7. The thickness of sand bed of a pressure filter is_____ cm
a) 10-20
b) 20-30
c) 30-50
d) 50-60
Answer
Answer: d [Reason:] The thickness of sand bed of a pressure filter is 50-60 cm, whereas the gravel layers of pressure filter are same as a rapid sand filter.
8. Which type of filter is used in treating swimming pool water?
a) Slow sand filter
b) Rapid sand filter
c) Dual media filter
d) Pressure filter
Answer
Answer: d [Reason:] The pressure filter is used for treating swimming pool water. It is also used for clarifying softened water at industrial plants.
9. The under drainage system in pressure consists of
a) Central drains connected to lateral drain
b) Wheeler system
c) Wagner system
d) Pipe grids, false bottom
Answer
Answer: d [Reason:] The under drainage system in pressure consists of pipe grids, false bottom and the washing of filter media is accomplished by reversing the flow by manipulating the valves in the pipe.
10. Consider the following statements regarding pressure filter
1. It is easy to inspect the under drainage system
2. It is not possible to provide time for chlorination in direct supply from it
3. It is not possible to observe the degree of back washing and the agitation process
Which of the above statement is correct?
a) 1 only
b) 2, 3
c) 1, 2, 3
d) 1, 3
Answer
Answer: b [Reason:] It is difficult to inspect, replace and clean the sand, gravel and under drainage system of pressure filter.
11. The rate of filtration of pressure filtration is ______ l/m2/hour.
a) 1000-5000
b) 5000-10000
c) 6000-8000
d) 6000-15000
Answer
Answer: d [Reason:] The rate of filtration of pressure filtration is 6000-15000l/m2/hour due to which it is used for treatment of swimming pool water.
Set 5
1. The loss of head during cleaning operation of a rapid sand filter is
a) 15-30cm
b) 1-5cm
c) 10-20cm
d) 10-25cm
Answer
Answer: a [Reason:] When cleaned bed is put into operation, the loss of head through it is 15-30cm and it goes on increasing as impurities are arrested in filter media.
2. The thickness of the suspended matter on top of the sand bed is
a) Directly proportional to head loss
b) Inversely proportional to head loss
c) Independent of the head loss
d) Directly proportional to the square of head loss
Answer
Answer: a [Reason:] As the thickness of suspended matter on top of the sand bed increases, the head loss is increased. So, it is directly proportional to head loss.
3. When the loss of the head exceeds the static head, the head becomes _____
a) Positive
b) Negative
c) Constant
d) Zero
Answer
Answer: b [Reason:] The head becomes negative when the loss of the head through the bed depth exceeds the static head.The negative head is the fall of liquid level in the piezometric tube below the center line of under drainage system.
4. What is the permissible negative head loss of a rapid sand filter?
a) 0.2-1m
b) 0.1-0.5m
c) 0.5-2m
d) 0.8-1.2m
Answer
Answer: d [Reason:] The permissible negative head loss of a rapid sand filter is 0.8-1.2m. When the permissible limits are reached, the filter run is terminated and the filter is back washed.
5. Which type of problem is caused in filter due to accumulation of solids on the top surface of filter media?
a) Clogging
b) Air binding
c) Sand incrustation
d) Sand leakage
Answer
Answer: a [Reason:] Clogging of bed is caused due to accumulation of solids on the top surface of filter media, which results in the formation of mud balls and cracking of the bed.
6. ______ are formed in filters due to insufficient washing of sand grains.
a) Sand boils
b) Mud balls
c) Clogging
d) Bubbles
Answer
Answer: b [Reason:] Mud balls are formed in filters due to insufficient washing of sand grains. Mud accumulates on the sand surface and form a dense mat.
7. The cracking of bed is more prominent
a) Near the wall junction
b) Outside the wall junction
c) Inside the wall junction
d) On the wall junction
Answer
Answer: a [Reason:] The cracking of bed is more prominent near the wall junction which allows dirty matter to penetrate into filter media which decreases the efficiency of filtration.
8. In which type of filtration problem, layers of gravel are displaced?
a) Clogging
b) Air binding
c) Sand incrustation
d) Sand leakage
Answer
Answer: d [Reason:] During Sand leakage, layers of gravel are displaced during back-washing. This can be minimized by proper proportioning of sand and gravel layers.
9. The tendency of jetting can be minimized by
a) Carbonating the water
b) Proportioning of layers of sand and gravel
c) Surface washing
d) Control of algae growth in the water
Answer
Answer: c [Reason:] The tendency of jetting can be minimized by surface washing. It can also be minimized by the use of an 8cm layer of coarse garnet between fine media and gravel.
10. _______ type of trouble in filter is caused by the released of dissolved air and gases from water.
a) Air binding
b) Clogging
c) Mud balls
d) Jetting
Answer
Answer: a [Reason:] Air binding is caused by the released of dissolved air and gases from water to form bubbles which occupy void space of the filter media and the drainage system.
11. How the problem of sand incrustation can be minimized?
a) Carbonating the water
b) Proportioning of layers of sand and gravel
c) Surface washing
d) Control of algae growth in the water
Answer
Answer: a [Reason:] The problem of sand incrustation can be minimized by carbonating the water so as to dissolve calcium carbonate that has deposited on sand grains.