Description : The algae dies out in the zone of A. Degradation B. Active decomposition C. Recovery D. Cleaner water
Last Answer : ANS: A
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 : Pick up the correct statement from the following: A. The maximum rate of storm runoff is called peak drainage discharge B. Rational method of estimating peak run off, may be used precisely for ... entire area starts contributing to the runoff, is called the time of concentration D. All the above
Last Answer : ANS: D
Description : The drainage area of a town is 12 hectares. Its 40% area is hard pavement ( K = 0.85), the 40% area is unpaved streets (K = 0.20) and the remaining is wooded areas (K = 0.15). Assuming the time of concentration ... 60) the maximum run off is A. 0.10 cumec B. 0.12 cumec C. 0.15 cumec D. 0.20 cumec
Last Answer : ANS: C
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 : 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
Last Answer : ANS: B
Description : For drainage pipes in buildings the test applied before putting them to use, is A. Water test B. Smoke test C. Straightness test D. All the above
Description : 3.0 ml of raw sewage is diluted to 300 ml. The D.O. concentration of the diluted sample at the beginning of the test was 8 mg/l. After 5 dayincubation at 20°C, the D.O. concentration was 5 mg/l. The BOD of raw sewerage is A. 100 mg/l B. 200 mg/l C. 300 mg/l D. 400 mg/l
Description : When drainage to sewage ratio is 20, the peak dry weather flow is A. 20% of the design discharge B. Slightly less than 5% of the design discharge C. Slightly more than 5% of the design discharge D. None of these
Description : For house drainage minimum gradient is A. 1 in 60 B. 1 in 80 C. 1 in 10 D. 1 in 400
Description : The stone ware sewers A. Are used for carrying sewage and drainage from houses B. Are manufactured from clays and shale C. After casting are dried and burnt at temperature 150°C, 700°C and 1200°C D. All the above
Description : In a city the ratio of the drainage to sewage is 20, the percentage discharge passing through non-monsoon periods, is A. 5 B. 10 C. 15 D. 20
Description : 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
Description : The rational formula for peak drainage discharge, was evolved by A. Fruhling B. Lloyd David C. Kuichling D. All of these
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
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
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 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 : Q No: 271 Pick up the correct statement from the following: A. Turbidity is more in strong sewage B. The black colour indicates septic sewage C. The sewage omits offensive odours after four hours D. All the above
Description : A safety lamp when inserted in the upper portion of a manhole causes flames. It indicates the presence of A. Carbondioxide gas B. Hydrogen sulphide gas C. Methane gas D. Petrol vapours
Description : Pick up the correct statement from the following: A. pH value indicates acidity and alkalinity of sewage B. In acidic sewage, the pH value is less than 7 C. In alkaline sewage, the pH value is more than 7 D. All the above
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
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 standard B.O.D. of water is taken for A. 1 day B. 2 days C. 3 days D. 5 days
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 : 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 : To test chemical oxygen demand (C.O.D.) of sewage, organic matter is oxidised by potassium dichromate in the presence of A. Hydrochloric acid B. Sulphuric acid C. Nitric acid D. Citric acid
Description : If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is A. 50 mg/l B. 100 mg/l C. 150 mg/l D. 250 mg/l
Description : A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is A. 100 B. 1000 C. 5000 D. 10000
Description : If the depletion of oxygen is found to be 5 ppm after incubating a 2.5% solution of sewage sample for 5 days at 21°C, B.O.D. of the sewage is A. 50 ppm B. 100 ppm C. 150 ppm D. 200 ppm
Description : If 2% solution of a sewage sample is incubated for 5 days at 20°C and depletion of oxygen was found to be 5 ppm, B.O.D. of the sewage is A. 200 ppm B. 225 ppm C. 250 ppm D. None of these
Description : In trickling filter, B.O.D. is reduced to A. 30 to 40% B. 40 to 60% C. 60 to 80% D. 80 to 90%
Description : Dried sewage after treatment is used as A. Fertilizer B. Building material C. Chemical for lowering B.O.D. D. Base material for paints
Description : R.M.O. expenses include A. Running expenses B. Maintenance expenses C. Operation expenses D. All the above
Description : Pick up the correct statement from the following: A. The water supply pipes carry pure water free from solid particles B. The water supply pipes get clogged if flow velocity is less than self ... carried up and down the hills and valleys D. The sewer pipes are generally laid along level hills
Description : A transport process in herbicide removal a).volatilization b).photo-decomposition c).chemical decomposition d).microbial degradation
Last Answer : a).volatilization
Description : To prevent settling down of sewage both at the bottom and on the sides of a large sewer, self-cleaning 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
Description : Pick out the wrong statement. (A) Catalytic converter is fitted in automobiles to reduce carbon monoxide concentration in exhaust emissions (B) Inhalation of pollutant carbon monoxide results ... D) Decomposition of plants containing chlorophyll is a natural source of carbon monoxide in atmosphere
Last Answer : (C) Sulphur dioxide is the main pollutant emitted from the exhaust of petrol driven automobiles
Description : The resting membrane potential of a cell a. is dependent on the permeability of the cell membrane to K+ being greater than the permeability to Na+ b. falls to zero immediately when Na+ ... the equilibrium potential for Na+ e. is markedly altered if the extracellular Na+ concentration is increased
Last Answer : is dependent on the permeability of the cell membrane to K+ being greater than the permeability to Na+
Description : Reclamation of saline soil which of the following practice is followed ? — a. Adequate drainage b. By good quality irrigation water c. Leaching of salts below root zone d. All of these
Last Answer : d. All of these
Description : A land is known as waterlogged (A) When the permanent wilting point is reached (B) When gravity drainage has ceased (C) Capillary fringe reaches the root zone of plants (D) None of the above
Last Answer : Answer: Option C
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