Description : If D.O. concentration falls down to zero in any natural drainage, it indicates the zone of A. Degradation B. Active decomposition C. Recovery D. Cleaner water
Last Answer : ANS: B
Description : Absence of fish along a river indicates (1) Zone of degradation (2) Zone of active decomposition (3) All zones of pollution (4) Zone of recovery
Last Answer : (1) Zone of degradation Explanation: Absence of fish along a river indicates zone of degradation.
Last Answer : Zone of degradation
Description : Assertion A. : Discharging the effluents from the oxidation ponds just up stream of lakes or reservoirs is undesirable. Reason (R) : The discharged algae get settled in the reservoirs and cause anaerobic decomposition and other ... of A C. A is true but R is false D. A is false but R is true
Last Answer : ANS: A
Description : In septic tanks, decomposition of organic bacteria, is done by A. Anaerobic bacteria B. Aerobic bacteria C. Both types of bacterias D. None of these
Description : The sewage treatment in septic tanks is due to A. Anaerobic decomposition B. Aerobic decomposition C. Parasitic decomposition D. None of these
Description : In very first stage of decomposition of the organic matter in sewage A. Nitrites are formed B. Nitrates are formed C. Carbondioxide is formed D. Ammonia is formed
Last Answer : ANS: D
Description : Pick up the correct statement from the following: A. Indore method of composting involves decomposition under aerobic conditions B. Bangalore method of composting involves decomposing under anaerobic conditions C ... the Bangalore method of compositing is a powdery mass called humus D. all of these
Description : The amount of oxygen consumed by the aerobic bacterias which cause the aerobic biological decomposition of sewage, is known A. Bio-Chemical Oxygen Demand (B.O.D.) B. Dissolved Oxygen (D.O.) C. Chemical Oxygen Demand (C.O.D.) D. None of these
Description : The sewage treatment units in which anaerobic decomposition of organic matter is used, are called A. Imhoff tanks B. Trickling filters C. Sludge sedimentation tanks D. None of these
Description : The detention time (t) of a settling tank, may be defined as the time required for A. A particle to travel along its length B. A particle to travel from top surface to bottom sludge zone C. The flow of sewage to fill the tank D. None of these
Last Answer : ANS: C
Description : A transport process in herbicide removal a).volatilization b).photo-decomposition c).chemical decomposition d).microbial degradation
Last Answer : a).volatilization
Description : Restriction endonucleases (a) are present in mammalian cells for degradation of DNA when the cell dies (b) are used in genetic engineering for ligating two DNA molecules (c) are used for in vitro DNA synthesis (d) are synthesized by bacteria as part of their defense mechanism.
Last Answer : (d) are synthesized by bacteria as part of their defense mechanism.
Description : Match column -I with column - II. Column-I Column-II A. Saprophyte (i) Symbiotic association of fungi with plant roots B. Parasite (ii) Decomposition of dead organic materials C. Lichens (iii) Living on living plants or animals D. ... (iii) (iv) (c) (iii) (ii) (i) (iv) (d) (ii) (i) (iii) (iv)
Last Answer : (a) (ii) (iii) (iv) (i)
Description : In case of sewer lines A. Water test is carried out to check water tightness of the joints B. Test for straightness is carried out with the help of a lamp and mirror C. Obstruction test is carried out with the help of smooth ball of diameter 13 mm D. All the above
Description : 54 Pick up the correct statement from the following: A. The ratio of the quantity of the diluting water to that of the sewage, is known as dilution factor B. The automatic purification of polluted ... phenomenon C. The photosynthesis is carried out in the presence of sun light D. All the above
Description : The standard B.O.D. of water is taken for A. 1 day B. 2 days C. 3 days D. 5 days
Description : Rate of flow of sewage is generally assumed A. More than the rate of water supply B. Equal to the rate of water supply C. Less than the rate of water supply D. At 150 litres per capita
Description : As compared to fresh river water, sea water contains oxygen A. 10% less B. 20% less C. 10% more D. 20% more
Description : Which one of the following tests is used for testing sewer pipes? A. Water test B. Ball test C. Mirror test D. All of these
Description : The angle subtended by the surface of sewer water with partial flow, at sewer centre is 120°, the depth of sewerage is A. 20 cm B. 25 cm C. 40 cm D. 50 cm
Description : Dry water flow in a combined sewer, is A. Industrial sewage B. Domestic sewage C. Storm water D. Inclusive of domestic and industrial sewage but excludes storm water
Description : For design purposes, the normal rate of infiltration of ground water into the sewer, is A. 500 litres/km/cm B. 1000 litres/km/cm C. 1500 litres/km/cm D. 2000 litres/km/cm
Description : The most effective arrangement for diverting excess storm water into a natural drainage, is A. Leaping weir B. Overflow weir C. Siphon spill way D. None of these
Description : A rain sanitary sewer is constructed to carry A. Sanitary sewage B. Storm sewage C. Surface water D. Ground water
Description : The settlement velocity of a solid (diameter 0.5 mm, specific gravity 1.75) in water having temperature 10°C, is A. 213.5 cm/sec B. 313.5 cm/sec C. 413.5 cm/sec D. 500 cm/sec
Description : The settlement of a particle in sedimentation tank, is affected by A. Velocity of flow B. Viscosity of water C. Size and shape of solid D. All the above
Description : The self-cleansing velocity of water flowing through pipe lines, is A. 2 metres/sec B. 1 metre/sec C. 0.5 metre/sec D. 0.25 metre/sec
Description : A nuisance is experienced in diluting water if dilution factor is less than A. 100 B. 60 C. 40 D. 20
Description : The water carried sewerage system removes A. Domestic sewage B. Industrial sewage C. Storm sewage D. All the above
Description : Pathogens (or pathogenic bacterias) in water may cause A. Typhoid B. Cholera C. Dysentery D. All the above
Description : WASTE WATER ENGINEERING Objective Questions with Answers Q No: 161 The quantity of liquid waste which flows in sewers during the period of rainfall, is known A. Sanitary sewage B. Industrial waste C. Storm sewage D. None of these
Description : WASTE WATER Engineering Objective Questions Pdf :: Q No: 151 The pH value of fresh sewage is usually A. Equal to 7 B. More than 7 C. Less than 7 D. Equal to zero
Description : The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is A. 0.05552 cumec B. 0.05554 cumec C. 0.05556 cumec D. 0.0556 cumec
Description : Chlorination of water is done for the removal of A. Bacterias B. Suspended solids C. Sediments D. Hardness
Description : The detention time of a circular tank of diameter d and water depth H, for receiving the sewage Q 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
Description : weight of water, the hydraulic mean depth of the sewer and the bed slope w is the unit of the sewer, then the tractive force exerted by flowing water, is A. w r S S B. w r1/2 C. w r S D. w r2/3
Description : The sewers A. Must be of adequate size to avoid over flow B. Must flow under gravity ½ to ¾ full C. Must be laid at least 2 to 3 m deep to collect /water from the basements D. All the above
Description : In the activated sludge process A. Aeration is continued till stability B. Aeration is done with an admixture of previously aerated sludge C. Sludge is activated by constant stirring D. Water is removed by centrifugal action
Description : Pick up the correct statement from the following: A. Inlets are provided on the road surface at the lowest point for draining rain water B. Inlets are generally provided at an interval of ... along straight roads C. Inlets having horizontal openings, are called horizontal inlets D. All the above
Description : Self-cleansing velocity is A. Velocity at dry weather flow B. Velocity of water at flushing C. Velocity at which no accumulation remains in the drains D. Velocity of water in a pressure filter
Description : The factor responsible for purification of sewage in river is A. Hydrology B. Dissolved oxygen in water C. Temperature D. All the above
Description : The detention period for plain sedimentation water tanks, is usually A. 4 to 8 hours B. 8 to 16 hours C. 16 to 24 hours D. 24 to 36 hours
Description : Water content of sewage is about A. 90 % B. 95 % C. 99 % D. 9.9 %
Description : Pick up the correct statement from the following: A. Hydrogen sulphide gas in excess, may cause corrosion of concrete sewers B. 4 ppm of Dissolved Oxygen (D.O.) is ensured before discharging the treated ... river C. Solubility of oxygen in sewage is 95% of that of distilled water D. All the above
Description : The sludge does not contain waste water from A. Bath rooms B. Wash basins C. Kitchen sinks D. Toilets
Description : If the peak discharge of a storm water drain (S.W. Drain) is expected to exceed 150 cumecs, the free board to be provided, is A. 100 cm B. 90 cm C. 80 cm D. 50 cm
Description : Dilution method of disposing of sewage, is not preferred to A. When sewage is fresh B. When diluting water has high dissolved oxygen content C. When diluting water is used for water supply near the point of sewage disposed D. When the diluting water is having flow currents
Description : Pick up the correct statement from the following: A. In treated sewage, 4 ppm of D.O. is essential B. Only very fresh sewage contains some dissolved oxygen C. The solubility of oxygen in sewage is 95% that is in distilled water D. All the above
Description : Traps A. Are water seals which prevent the entry of foul gases B. Are used to trap the rats entering sewers C. Dissolve the foul gases D. Create symphonic action to increase the quick disposal of sewerage