Description : The gas evolved in sewers is A. Carbondioxide B. Hydrogen sulphide C. Methane D. All of these
Last Answer : ANS: D
Description : In sewers the gas generally found, is A. Hydrogen sulphide (H2S) B. Carbon dioxide (CO2) C. Methane (CH4) 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
Last Answer : ANS: C
Description : Lead acetate test in sewer manhole is done to test the presence of A. Methane gas B. Hydrogen sulphide C. Carbondioxide gas D. Diesel vapours
Last Answer : ANS: B
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. 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 : Which of the following gases is having the widest explosion limit (about 2 to 81% gas in gas-air mixture), rendering it the property of the most explosive gas? (A) Hydrogen (B) Acetylene (C) Carbon monoxide (D) Ammonia
Last Answer : (B) Acetylene
Description : __________ has the widest inflammability limit (explosion limit) of all the gases. (A) Hydrogen (B) Carbon monoxide (C) Acetylene (D) Methane
Last Answer : (C) Acetylene
Description : For large sewers, maximum distance between manholes may be A. 50 m B. 100 m C. 200 m D. 300 m
Description : Setting out the alignments of sewers may start from A. City B. Out-fall C. Tail end D. Any point
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
Last Answer : ANS: A
Description : Pick up the correct statement from the following: A. Small sewers are cleaned by flushing B. Medium sewers are cleaned by cane rodding C. Medium sewers may be cleaned by pills D. All the above
Description : Which one of the following gases is most significant as air pollutant? A. Carbondioxide B. Oxygen C. Nitrogen D. Sulphur-dioxide
Description : During purification process of sewage the gas given off, is A. Carbon dioxide B. Hydrogen C. Ammonia D. All the above
Description : Presence of volatile compounds like gasoline, oil, alcohol, ether etc. in municipal sewers may cause (A) Explosion (B) Non biodegradable foam (C) Undesirable plant growth (D) Corrosion
Last Answer : (A) Explosion
Description : If a paper moistened with lead acetate for five minutes when placed in manhole turns black. The sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Description : If the flame of a miner’s safety lamp in a manhole extinguishes within 5 minutes, the sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Description : Pick up the incorrect statement from the following: A. The process of decomposing the organic matter under controlled anaerobic conditions, is called sludge digestion B. Sludge digestion is carried ... contain 75% carbon dioxide D. The gases produced in sludge digestion process, contain 75% methane
Description : If the flame of a miner’s safety lamp in the upper layers of the sewer forms an explosive, the sewer certainly contains A. Hydrogen sulphide B. Carbon dioxide C. Methane D. Oxygen
Description : Which one of the following group of gases contribute to the "Green House Effect"? (1) Carbon dioxide and Methane (2) Ammonia and Ozone (3) Carbon monoxide and Sulphur dioxide (4) Carbon tetrailouride and Nitrous oxide
Last Answer : (1) Carbon dioxide and Methane Explanation: The primary greenhouse gases in the Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone. When ranked by their direct contribution to the greenhouse ... 72 %, Carbon Dioxide: 9- 26 %, Methane: 4-9 % and Ozone: 3-7 %.
Description : Which one of the following group of gases contribute to the “Green House Effect”? (1) Carbon dioxide and Methane (2) Ammonia and Ozone (3) Carbon monoxide and Sulphur dioxide (4) Carbon tetraflouride and Nitrous oxide
Last Answer : Carbon dioxide and Methane
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 small sewers are cleaned by A. Flushing B. Cane rodding C. Wooden pills D. None of these
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 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 : The laying of sewers is done with A. Magnetic compass B. Theodolite C. Level D. Clinometer
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 : 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
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 underground sewers are more subjected to A. Tensile force B. Compressive force C. Bending force D. Shearing force
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 : 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
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