Dear Readers, Welcome to Environmental Engineering Objective Questions have been designed specially to get you acquainted with the nature of questions you may encounter during your Job interview for the subject of Environmental Engineering MCQs. These objective type Environmental Engineering questions are very important for campus placement test and job interviews. As per my experience good interviewers hardly plan to ask any particular question during your Job interview and these model questions are asked in the online technical test and interview of many IT & Non IT Industries.
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 the correct explanation of A.
c) A is true but R is false.
d) A is false but R is true.
Ans: a
i) climatic conditions
ii) quality of water
iii) distribution pressure
The correct answer is
a) only (i)
b) both (i) and (ii)
c) both (i) and (iii)
d) all (i), (ii) and (iii)
Ans: d
a) use of metering system
b) good quality of water
c) better standard of living of the people
d) hotter climate
Ans:a
a) 1.5
b) 1.8
c) 2.0
d) 2.7
Ans:a
a) 100000m3
b) 150000m3
c) 180000m3
d) 270000 m3
Ans:d
a) maximum daily demand
b) maximum hourly demand
c) average daily demand
d) maximum hourly demand on maximum day
Ans:d
a) lesser value
b) higher value
c) same value
d) accurate value
Ans:a
a) 9500
b) 9800
c) 10100
d) 10920
Ans:d
a) arithmetical increase method
b) geometrical increase method
c) incremental increase method
d) graphical method
Ans:b
a) at a distance R from the well
b) close to the well
c) at a distance R/2 from the well
d) none of the above
where R is the radius of influence
Ans:b
a) aquifers
b) aquiclude
c) filters
d) intakes
Ans:d
a) N = y + R
b) y = N + R
c) R = N + y
d) R > (N + y)
Ans:a
a) air relief valve
b) reflux valve
c) pressure relief valve
d) sluice valve
Ans:b
a) 5 litres/sec
b) 50 litres/sec
c) 500 litres/sec
d) 1000 litres/see
Ans:b
a) more depth
b) less depth
c) more discharge
d) less discharge
Ans:c
a) suspended impurities
b) dissolved impurities
c) both suspended and dissolved impuri¬ties
d) none of the above
Ans:a
a) contains pathogenic bacteria
b) consists of undesirable substances rendering it unfit for drinking and domestic use
c) is safe and suitable for drinking and domestic use
d) is contaminated
Ans:b
a) dysentery
b) cholera
c) typhoid
d) maleria
Ans:d
a) carbon dioxide
b) oxygen
c) hydrogen
d) nitrogen
Ans:a
a) 0.1 ppm
b) 0.01 ppm
c) 0.001 ppm
d) 0.0001 ppm
Ans:c
a) 0.1 mg/litre
b) 1.5 mg/litre
c) 5 mg/litre
d) 10 mg/litre
Ans:b
a) hardness in water
b) turbidity in water
c) dissolved oxygen in water
d) residual chlorine in water
Ans:a
i) presumptive coliform test
ii) confirmed coliform test
iii) completed coliform test The correct answer is
a) only (i)
b) both (i) and (ii)
c) both (i) and (iii)
d) all (i), (ii) and (iii)
Ans:d
a) calcium carbonate
b) magnesium carbonate
c) sodium carbonate
d) calcium hydroxide
Ans:a
a) 2
b) 5
c) 7
d) 10
Ans:a
a) standard silica scale
b) standard cobalt scale
c) standard platinum scale
d) platinum cobalt scale
Ans:a
a) 10 ppm
b) 20 ppm
c) 30 ppm
d) 50 ppm
Ans:a
a) starch iodide method
b) orthotolidine method
c) both (a) and (b)
d) none of the above
Ans:c
a) dissolved oxygen
b) residual chlorine
c) biochemical oxygen demand
d) dose of coagulant
Ans:b
a) total alkalinity
b) total hardness
c) total hardness - total alkalinity
d) non carbonate hardness
Ans:a
a) 0.01 to 0.05 ppm
b) 0.05 to 0.5 ppm
c) 0.5 to 1.0 ppm
d) 1.0 to 5.0 ppm
Ans:b
a) 1 mg/litre
b) 10 mg/litre
c) 100 mg/litre
d) 1000 mg/litre
Ans:b
a) 5 to 10 cm/sec.
b) 15 to 30 cm/sec.
c) 15 to 30 cm/minute
d) 15 to 30 cm/hour
Ans:c
a) B
b) 2B
c) 4B
d) 8B
where B is the width of the tank
Ans:c
a) 500 to 750 litres/hour/ m2
b) 1000 to 1250 litres/hour/ m2
c) 1250 to 1500 litres/hour/m2
d) 1500 to 2000 litres/hour/m2
Ans:a
a) 10 to 25
b) 50
c) 75
d) 100
Ans:c
a) depth of tank
b) surface area of tank
c) both depth and surface area of tank
d) none of the above
Ans:b
a) particle size is decreased
b) the surface area of tank is increased
c) the depth of tank is decreased
d) none of the above
Ans:d
a) increasing the depth of tank
b) decreasing the depth of tank
c) increasing the surface area of tank
d) decreasing the surface area of tank
Ans:c
a) less and more
b) less and less
c) more and less
d) more and more
Ans:c
i) increase in turbidity of water
ii) decrease in turbidity of water
iii) increase in temperature of water
iv) decrease in temperature of water
The correct answer is
a) (i) and (ii)
b) (i)and(iv)
c) (ii) and (iii)
d) (ii) and (iv)
Ans:b
a) 2 to 4
b) 4 to 6
c) 6 to 8
d) 8 to 10
Ans:c
a) 1 to 2 minutes
b) 30 to 45 minutes
c) 2 to 6 hours
d) 2 to 6 days
Ans:c
a) does not require alkalinity in water for flocculation
b) does not affect pH value of water
c) increases pH value of water
d) decreases pH value of water
Ans:d
a) sulphuric acid
b) copper sulphate
c) lime
d) sodium permanganate
Ans:c
a) dissolved organic substances
b) dissolved solids and dissolved gases
c) floating solids and dissolved inorganic solids
d) bacteria and colloidal solids
Ans:d
a) 50 to 60
b) 100 to 150
c) 500 to 600
d) 1400 to 1500
Ans:a
a) 0.25 to 0.35 mm
b) 0.35 to 0.60 mm
c) 0.60 to 1.00 mm
d) 1.00 to 1.80 mm
Ans:a
i) slower filtration rate
ii) higher filtration rate
iii) lesser efficiency in removal of bacteria
iv) higher efficiency in removal of bacteria The correct answer is
a) (i) and (ii)
b) (ii) and (iii)
c) (i) and (iv)
d) (ii) and (iv)
Ans:c
Reason R : The sand used in slow sand filters is finer than that in rapid sand filters.
Select your answer based on the coding system given below:
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 the correct explanation of A.
c) A is true but R is false.
d) A is false but R is true.
Ans:a
a) excessive negative head
b) mud ball formation
c) higher turbidity in the effluent
d) low temperature
Ans:a
a) 0.2 to 0.4
b) 0.4 to 1.0
c) 2 to 4
d) 5 to 7
Ans:c
a) 24 - 48 hours
b) 10-12 days
c) 2-3 months
d) 1-2 year
Ans:c
a) less than that of slow sand filters
b) in between the filtration rate of slow sand filters and rapid sand filters
c) greater than that of rapid sand filters
d) equal to that of slow sand filters
Ans:c
a) to increase the filtration slow sand filters capacity of
b) to increase the filtration rapid sand filters capacity of
c) for isolated buildings like pools, hotels etc swimming
d) all of the above
Ans:a
i) scraping and removal in filters slow sand
ii) back washing in slow sand filters
iii) scraping and removal in filters rapid sand
iv) back washing in rapid sand filters
The correct answer is
a) (i) and (ii)
b) (ii) and (iii)
c) (i) and (iv)
d) (ii) and (iv)
Ans:c
a) removal of turbidity
b) removal of hardness
c) killing of disease bacteria
d) complete sterilisation
Ans:c
i) decreasing the time of contact
ii) decreasing the temperature of water
iii) increasing the temperature of water The correct answer is
a) only (i)
b) both (i) and (ii)
c) both (i) and (iii)
d) only (iii)
Ans:d
a) applied chlorine
b) residual chlorine
c) sum of applied and residual chlorine
d) difference of applied and residual chlorine
Ans:d
a) prechlorination
b) post chlorination
c) super chlorination
d) break point chlorination
Ans:c
a) 10 to 15
b) 20 to 25
c) 30 to 35
d) 40 to 50
Ans:c
a) prechlorination
b) super chlorination
c) dechlorination
d) hypochlorination
Ans:d
a) ultra violet rays treatment
b) lime treatment
c) by using potassium permanganate
d) chlorination
Ans:a
a) carbon dioxide
b) bleaching powder
c) sulphur dioxide
d) chloramines
Ans:c
a) increases
b) decreases
c) remains unaffected
d) none of the above
Ans:a
a) smaller
b) larger
c) same
d) none of the above
Ans:a
a) reduced at higher pH value of water
b) unaffected by pH value of water
c) increased at higher pH value of water
d) highest at pH value equal to 7
Ans:a
a) only carbonate hardness is removed
b) only non-carbonate hardness is re-moved
c) lime reduces the carbonate hardness and soda-ash removes the non-carbo¬nate hardness
d) lime reduces the non-carbonate hard-ness and soda-ash removes the carbo¬nate hardness
Ans:c
a) it is unsuitable for turbid and acidic water
b) huge amount of precipitate is formed which creates a disposal problem
c) the effluent cannot be reduced to zero hardness
d) it is unsuitable for softening the water of excessive hardness
Ans:b
a) sodium sulphate
b) copper sulphate
c) sodium chloride
d) calcium chloride
Ans:b
a) disinfection
b) removing hardness
c) removing odours
d) removing corrosiveness
Ans:c
a) heavier
b) stronger
c) costlier
d) less susceptible to corrosion
Ans:b
a) dead end system
b) grid iron system
c) radial system
d) ring system
Ans:a
a) ring system
b) dead end system
c) radial system
d) grid iron system
Ans:c
a) grid iron system
b) dead end system
c) ring system
d) radial system
Ans:a
a) steel
b) cast iron
c) copper
d) reinforced cement concrete
Ans:b
i) involves successive trials
ii) takes economic aspects into account
iii) is time consuming
The correct answer is
a) only (i)
b) (i)and(ii)
c) (i) and (iii)
d) all are correct
Ans:c
a) circle method
b) equivalent pipe method
c) electrical analysis method
d) Hardy cross method
Ans:a
a) circle method
b) equivalent pipe method
c) Hardy cross method
d) electrical analysis method
Ans:b
a) check valve
b) sluice valve
c) safety valve
d) scour valve
Ans:b
a) reflux valve
b) sluice valve
c) air relief valve
d) pressure relief valve
Ans:a
a) at street corners to control the flow of water
b) at every depression and dead ends to drain out the waste water that may collect there
c) at the foot of rising main along the slope to prevent back running of water
d) at every summit of rising mains
Ans:b
a) house sewer
b) lateral sewer
c) intercepting sewer
d) submain sewer
Ans:b
a) house sewer
b) lateral sewer
c) main sewer
d) submain sewer
Ans:a
a) separate system
b) combined system
c) partially combined system
d) partially separate system
Ans:a
a) 100 litres
b) 135 litres
c) 165 litres
d) 200 litres
Ans:b
a) 10 years
b) 25 years
c) 50 years
d) 75 years
Ans:b
a) circular sewer
b) egg shaped sewer
c) rectangular sewer
d) none of the above
Ans:b
a) separate system
b) combined system
c) partially separate system
d) partially combined system
Ans:b
a) is cheaper in initial cost than dry conservancy system
b) requires treatment before disposal
c) creates hygenic problem
d) all of the above
Ans:b
a) 4 mm/hr
b) lOmm/hr
c) 20 mm/hr
d) 40 mm/hr
Ans:d
a) the time taken by rainfall water to run from most distant point of water shed to the inlet of sewer
b) the time required for flow of water in sewer to the point under consideration
c) sum of (a) and (b)
d) difference of (a) and (b)
Ans:c
a) much greater than 1
b) slightly less than 1
c) equal to 1
d) slightly greater than 1
Ans:d
a) less than 1.0 m/sec
b) 1.0 m/sec to 1.2 m/sec
c) 1.5 m/sec to 2.0 m/sec
d) 3.0 m/sec to 3.5 m/sec
Ans:b
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
Ans:a
a) equal to dry weather flow (DWF)
b) 2xDWF
c) 3 x DWF
d) 6xDWF
Ans:d
a) equal to rainfall
b) rainfall + DWF
c) rainfall + 2 DWF
d) rainfall + 6 DWF
Ans:c
a) 15 cm and 100 cm
b) 15 cm and 300 cm
c) 30 cm and 450 cm
d) 60 cm and 300cm
Ans:b
a) less strength
b) difficulty in construction
c) difficulty in transportation due to heavy weight
d) less life
Ans:c
a) rectangular section
b) circular section
c) standard form of egg shaped sewer
d) modified egg shaped section
Ans:b
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
Ans:b
a) grade of sewer
b) length of sewer
c) hydraulic mean depth of sewer
d) roughness of sewer
Ans:b
a) equal to HMD when flowing full
b) less than HMD when flowing full
c) greater than HMD when flowing full
d) none of the above
Ans:c
a) to decrease it
b) to increase it
c) fluctuating
d) nil
Ans:b
a) circular brick sewer
b) circular cast iron sewer
c) semi-elliptical sewer
d) horse-shoe type sewer
Ans:a
a) circular sewer
b) egg shaped sewer
c) horse-shoe type sewer
d) semi-elliptical sewer
Ans:b
a) acidic and alkaline
b) alkaline and acidic
c) both acidic
d) both alkaline
Ans:b
a) nitrification
b) chlorination
c) oxidation
d) none of the above
Ans:b
a) higher temperature
b) sunlight
c) satisfying oxygen demand
d) none of the above
Ans:d
a) 5-10 years
b) 15-20 years
c) 30-40 years
d) 40-50 years
Ans:b
a) specific gravity of solid particles
b) size of particles
c) depth of tank
d) temperature of liquid
Ans:c
a) 20°C - 1day
b) 25°C- 3day
c) 20°C - 5day
d) 30°C- 5day
Ans:c
a) TOD>BOD>COD
b) TOD>COD>BOD
c) BOD>COD>TOD
d) COD>BOD>TOD
Ans:b
a) 5 day BOD is the ultimate BOD.
b) 5 day BOD is greater than 4 day BOD keeping other conditions same.
c) 5 day BOD is less than 4 day BOD keeping other conditions same.
d) BOD does nof depend on time.
Ans:c
a) 1000
b) 4000
c) 100000
d) 400000
Ans:d
a) directly proportional to BOD satisfied
b) directly proportional to BOD remain-ing ,
c) inversely proportional to BOD satisfied
d) inversely proportional to BOD re-maining
Ans:b
a) 1/3
b) 2/3
c) 3/4
d) 1.0
Ans:b
a) 100 ppm
b) 200 ppm
c) 300 ppm
d) 400 ppm
Ans:b
a) 1 ppm
b) 4 ppm
c) 10 ppm
d) 40 ppm
Ans:b
a) 1
b) 100
c) infinite
d) zero
Ans:b
a) maximum at noon
b) minimum at noon
c) maximum at midnight
d) same throughout the day
Ans:a
a) presence of oxygen only
b) absence of oxygen only
c) presence as well as in absence of oxygen
d) presence of water
Ans:c
a) inlet
b) manhole
c) drop manhole
d) catch basin
Ans:b
a) maximum flow only
b) minimum flow only
c) average flow only
d) maximum and minimum flow
Ans:d
a) maximum flow only
b) minimum flow only
c) average flow only
d) maximum and minimum flow
Ans:c
a) a theodolite
b) a compass
c) sight rails and boning rods
d) a plane table
Ans:c
a) septic conditions
b) dissolved oxygen
c) chlorine
d) nitrogen
Ans:a
a) grit chambers
b) detritus tanks
c) skimming tanks
d) sedimentation tanks
Ans:c
a) 1 minute
b) 5 minutes
c) 2-4 hours
d) 12 hours
Ans:a
a) sludge digestion tank
b) sedimentation tank
c) activated sludge treatment
d) trickling filters
Ans:a
i) settling tank
ii) digestion tank
iii) aeration tank
The correct answer is
a) only (i)
b) (i) and (ii)
c) (i) and (iii)
d) only (iii)
Ans:b
a) oxidation pond
b) oxidation ditch
c) aerated lagoons
d) trickling filters
Ans:b
a) aerobic only
b) anaerobic only
c) aerobic in lower compartment and anaerobic in upper compartment
d) anaerobic in lower compartment and aerobic in upper compartment
Ans:d
a) aerobic bacteria only
b) algae only
c) dual action of aerobic bacteria and anaerobic bacteria
d) sedimentation
Ans:c
a) 4-8 hours
b) 24 hours
c) 10 to 15 days
d) 3 months
Ans:c
a) sludge digestion
b) sludge disposal
c) sedimentation
d) filtration
Ans:b
a) large area is required for construction
b) maintenance and operation cost are high
c) BOD removal is very low
d) none of the above
Ans:a
a) 4.5 to 6.0
b) 6.5 to 8.0
c) 8.5 to 10.0
d) 10.5 to 12.0
Ans:b
a) percentage of sludge by volume to percentage of suspended solids by weight
b) percentage of sludge by volume to percentage of total solids by weight
c) percentage of suspended solids by weight to percentage of sludge by volume
d) percentage of total solids by weight to percentage of sludge by volume
Ans:a
a) 0 to 50
b) 50 to 150
c) 150 to 350
d) 350 to 500
Ans:c
a) 0
b) 1
c) infinity
d) none of the above
Ans:b
a) X/4
b) X/2
c) X
d) 2X
Ans:b
a) vent pipe
b) antisiphonage pipe
c) waste pipe
d) soil pipe
Ans:b
a) one soil pipe, one waste pipe and one vent pipe
b) one soil pipe, two waste pipes and one vent pipe
Ans:c
a) waste pipe
b) soil pipe
c) vent pipe
d) antisiphonage pipe
Ans:a
a) nitrogen
b) carbon dioxide
c) hydrogen sulphide
d) methane
Ans:d
a) parasitic
b) saprophytic
c) pathogenic
d) anaerobic
Ans:b
a) reducing the excessive flow in sewers
b) disposing of sludge
c) increasing the capacity of storage re-servoirs
d) increasing flow of sewage through imhoff tanks
Ans:b
a) oxidation
b) dehydration
c) reduction
d) alkalinization
Ans:a
a) cipoletti weir
b) broadcrested weir
c) leaping weir
d) submerged weir
Ans:c