Description : Which one of the following resists hydrogen sulphide corrosion? A. R.C.C. B. Glazed stone wares C. Asbestos cement D. Glazed ware
Last Answer : ANS: D
Description : The underground sewers are more subjected to A. Tensile force B. Compressive force C. Bending force D. Shearing force
Last Answer : ANS: B
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 : 221 For non-scouring velocity 5 m/sec, the type of sewers generally preferred to, is A. Cast iron sewers B. Cement concrete sewers C. Glazed bricks sewers D. Stone ware sewers
Last Answer : ANS: C
Description : In sewers the highest non-scouring velocity is achieved in A. Glazed bricks sewers B. Cast iron sewers C. Cement concrete sewers D. Stone ware sewers
Last Answer : ANS: A
Description : Cement concrete sewers are only suitable if non-scouring velocity is between A. 2.5 to 3.0 m/sec B. 3.0 to 4.0 m/sec C. 3.5 to 4.5 m/sec D. 4.5 to 5.5 m/sec
Description : The pressure exerted by A. The sewage when running full from inside, is called internal pressure B. The internal pressure if any, causes tensile stress in the pipe material C. Pressure sewers are designed to be safe in tension D. All the above
Description : The asbestos cement pipes are generally laid A. Horizontally B. Vertically C. At an angle of 30° D. At an angle of 60°
Description : The drop man holes are generally provided in sewers for A. Industrial areas B. Large town ships C. Hilly town ships D. Cities in plains
Description : Large diameter sewers subjected to external pressure alone, are reinforced A. Near the inner surface of the pipe B. Near the outer surface of the pipe C. Both A. and B. D. With elliptical cage
Description : For large sewers, maximum distance between manholes may be A. 50 m B. 100 m C. 200 m D. 300 m
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 : The presence of free ammonia in sewage, is detected by A. Boiling B. Adding potassium permanganate C. Adding sulphuric acid D. Phenol-di-sulphuric acid
Description : For detecting the nitrites in the sewage, the matching colour may be developed by adding A. Potassium permanganate B. Sulphuric acid and napthamine C. Phenol-di -sulphuric acid potassium hydroxide D. None of these
Description : For detecting the nitrates in sewage, the colour may be developed by adding A. Potassium permanganate B. Sulphuric acid and napthamine C. Phenol-di -sulphuric acid and potassium hydroxide D. None of these
Description : Sewer manholes are generally provided at A. The change of gradient B. The change of direction C. The junctions of sewers D. All of these
Description : The sewerage system originates from A. House sewers B. Lateral sewers C. Branch sewers D. Main sewers
Description : The gas evolved in sewers is A. Carbondioxide B. Hydrogen sulphide C. Methane D. All of these
Description : The small sewers are cleaned by A. Flushing B. Cane rodding C. Wooden pills D. None of these
Description : In sewers the gas generally found, is A. Hydrogen sulphide (H2S) B. Carbon dioxide (CO2) C. Methane (CH4) D. All the above
Description : The gradient of sewers depends upon A. Velocity of flow B. Diameter of the sewer C. Discharge D. All the above
Description : In olden days the type of section adopted in trunk and out fall sewers was A. Parabolic shaped B. Horse shoe shaped C. Egg shaped D. Circular shaped
Description : With self cleansing velocity in sewers A. Silting occurs at bottom B. Scouring occurs at bottom C. Both silting and scouring occur at bottom D. Neither silting nor scouring occurs at bottom
Description : Clogging of sewers, is caused due to A. Silting B. Low discharge C. Greasy and oily matters D. All the above
Description : The laying of sewers is done with A. Magnetic compass B. Theodolite C. Level D. Clinometer
Description : For trunk sewers more than 1.25 m in diameter, the ratio of the maximum daily sewage flow to the average daily sewage flow is assumed A. 1.5 B. 2.0 C. 2.5 D. 3.0
Description : Boussinesq’s equation for ascertaining unit pressure at a depth on sewers due to traffic loads, is A. pt = 3H3p/2 Z5 B. pt = 2H3p/3 Z5 C. pt = 3H3p/2Z5 D. pt = 2 3p/3Z5
Description : The most efficient cross section of sewers in a separate sewerage system is A. Parabolic B. Circular C. Rectangular D. New egged
Description : The minimum recommended diameter of sewers, is A. 5 cm B. 10 cm C. 15 cm D. 20 cm
Description : The suitable cross-section of sewers to carry combined flow, is A. Circular B. Egg shaped C. Rectangular D. Horse shoe shaped
Description : The maximum spacing of manholes specified by Indian standard in sewers upto 0.3 m diameter is A. 20 m B. 30 m C. 45 m D. 75 m
Description : For trunk and out-fall, the type of sewers generally used, is A. Standard egg shaped B. Circular shaped C. Horse shoe shaped D. Parabolic shaped
Description : The maximum diameter of sewers adopted in the designs is A. 1.0 m B. 2.0 m C. 3.0 m D. 4.0 m
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 : Q No: 191 Design period of 40 to 50 years is adopted for A. Branch sewers B. Main sewers C. Trunk sewers D. All the above
Description : In circular sewers if depth of flow is 0.2 times the full depth, the nominal gradient, A. Is only provided B. Is doubled C. Is trebled D. Is not enough
Description : In sewers designed with self cleansing velocity, A. The bottom is silted B. The bottom is scoured C. Both silting and scouring occur at the bottom D. Neither silting nor scouring occurs at the bottom
Description : For sewers, inverted siphon is provided for A. One pipe B. Two pipes C. Three pipes D. Four pipes
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 : In a residential colony, sewers of diameters 100 mm, 150 mm and 225 mm were laid with a gradient 1 in 120. Which portion of the sewage system does not choke in due course of time? A. 100 mm dia. B. 150 mm dia. C. 225 mm dia. D. All of these
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 : Pick up the incorrect size of stone ware sewers A. 52.5 cm B. 67.5 cm C. 82.5 cm D. None of these
Description : Setting out the alignments of sewers may start from A. City B. Out-fall C. Tail end D. Any point
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 : For design of sewers, percentage of sewage discharge is assumed A. 65 to 70% B. 70 to 75% C. 75 to 80% D. 85%
Description : Q No: 101 are available in size Stoneware sewers A. 10 cm B. 15 cm C. 20 cm D. All the above
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 most efficient cross-section of sewers in a combined sewerage system is A. Parabolic B. Circular C. Rectangular D. New egged
Description : Sewer ventilating columns are generally placed at A. Distances 150 m to 300 m B. Upper ends of branch sewers C. Every change in the size of sewers D. All the above
Description : Pick up the correct statement from the following: A. The circular section of sewers provides maximum hydraulic mean depth B. The circular sewers are provided for separate sewerage system C. The circular sewers work efficiently if the sections run at least half full D. All the above