Civil Engineering – Waste water Engineering Mock test – 1 Welcome to your Waste water Engineering Mock test - 1 Take an exciting test in Waste water Engineering You have only 20 mins to complete the test (33 Questions) Wish you all the best!!! Name Email Chlorination of water is done for the removal of A. bacterias B. suspended solids C. sediments D. hardness.For evaporation and measurement of settlable solids, the apparatus used, is A. a jar B. a breaker C. a test tube D. an Imhoff cone.The non-clog pump which permits solid matter to pass out with the liquid sewage, is A. centrifugal pump B. reciprocating pump C. pneumatic ejector D. none of these.The ratio of maximum sewage flow to average sewage flow for mains up to 1 m in diameter, is A. 1.5 B. 2.0 C. 3.0 D. 4.0In R.C. sewer pipes, the percentage longitudinal reinforcement to the cross-sectional area of concrete is kept A. 10.0 B. 5.0 C. 2.0 D. 0.25Self-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.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.If the diameter of sewer is 225 mm, the gradient required for generating self cleansing velocity, is A. 1 in 60 B. 1 in 100 C. 1 in 120 D. none of these.In SI units the power of sound is represented in A. kgs B. joules C. neutons D. watts.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.Removal of oil and grease from sewage, is known A. screening B. skimming C. filtration D. none of these.Dilution method of disposing off 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 currentsFor house drainage minimum gradient is A. 1 in 60 B. 1 in 80 C. 1 in 10 D. 1 in 400For the COD test of sewage, organic matter is oxidised by K2Cr207 in the presence of A. H2SO4 B. HNO3 C. HCl D. none of these.For the survival of fish in a river stream, the minimum dissolved oxygen is prescribed A. 3 PPm B. 4 PPm C. 5 PPm D. 10 ppm.In primary sedimentation, the 0.2 mm inorganic solids get separated if specific gravity is A. 2.25 B. 2.50 C. 2.55 D. 2.65 E. 2.75House connections to the laterals is generally made by A. R.C.C. B. P.C.C. C. Cast iron D. Glazed stonewares.The screens are fixed A. perpendicular to the direction of flow B. parallel to the direction of flow C. at an angle 30° to 60° to the direction of flow D. none of these.Disposal to sewage in large cities, is done in A. irrigation B. dilution C. oxidation D. putrifaction.A rainfall may be classified as acidic if its pH value is less or equal to A. 6 B. 7 C. 5 D. 6.5The asbestos cement pipes are generally laid A. horizontally B. vertically C. at an angle of 30° D. at an angle of 60°.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 water qualities. 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 a correct explanation of A C. A is true but R is false D. A is false but R is true.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.For treating the sewage of a large city, you will recommend A. a sedimentation tank and an activated sludge treatment plant B. a plant consisting of Imhoff tanks with low rate trickling filters C. sedimentation tanks with high rate trickling filters D. none of these.The coagulant widely used for sewage treatment, is A. alum B. ferric chloride C. ferric sulphate D. chlorinated copperas.The ratio of minimum hourly flow to the average flow of sewage is A. 1/4 B. 1/3 C. 1/2 D. 3/4If D is the diameter of upper circular portion, the overall depth of a standard egg shaped section, is A. D B. 1.25 D C. 1.5 D D. 1.75 D E. 2 D.The gas which may cause explosion in sewers, is A. carbondioxide B. methane C. ammonia D. carbon monoxide.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.An inverted siphon is designed generally for A. one pipe B. two pipes C. three pipes D. four pipes.The rate of accumulation of sludge in septic tanks is recommended as A. 30 litres/person/year B. 25 litres/person/year C. 30 litres/person/month D. 25 litres/person/month.Flocculated particles do not change their A. size B. shape C. weight D. none of these.The minimum recommended diameter of sewers, is A. 5 cm B. 10 cm C. 15 cm D. 20 cm.