63 Water Supply & Sanitation Chapter Wise McQ Test of 25 Question #23 Water Supply & Sanitation Chapter Wise McQ Test of 25 Question for PSC, NEC, UPSC, SSC and Many more. 1 / 25 1. The optimum maximum and minimum velocities for maximum and minimum flows of sewer respectively in m/sec are …… A. 0.90 and 0.45 B. 0.45 and 0.90 C. 1.00 and 0.50 D. 2.00 and 1.00 2 / 25 2. The self-cleaning velocity normally adopted for sewage is A. less than 1m/sec B. 1.0 m/sec to 1.2 m/sec C. 1.5 m/sec to 1.2 m/sec D. more than 2.0 m/sec 3 / 25 3. Larger velocities in drain and sewers should be avoided to …… A. Keep solid matter moving B. Protect erosion of inside materials of sewer C. Keep minimum gradient D. Ensure smooth flow of water 4 / 25 4. When limiting non-scouring velocity is 5 m/sec of the sewer generally used is A. Stone water sewer B. Cast iron sewer C. Brick sewer D. Glazed brick sewer 5 / 25 5. The highest non-scouring velocity in sewer may be allowed in A. Cast iron sewer B. Glazed brick sewer C. Cement concrete D. Stone ware sewer 6 / 25 6. Non-scouring velocity in concrete sewer is…….. A. 2.5 to 3.0 m/sec B. 2.5 to 3.5 m/sec C. 1.5 to 2.5 m/sec D. 0.6 to 1.2 m/sec 7 / 25 7. The velocity of flow does not depend on A. Grade of sewer B. Hydraulic mean depth of sewer C. Roughness of sewer D. Length of sewer 8 / 25 8. In Cheyz’s formula v=c√𝑚𝑠 for calculating the velocity of flow in circular sewer, the Cheyz’s constant c depends upon A. Size of the sewer B. Shape of the sewer C. Roughness of the sewer D. All of the above 9 / 25 9. The gradient to be provided for sewers depended upon A. The diameter of the sewer B. The discharge C. Sewer pipe material D. All of the above 10 / 25 10. The gradient of sewer is A. Given in the direction of natural slope of ground B. Given in the opposite direction of naturals slope ground C. Zero D. More than 1 in 20 11 / 25 11. For 150mm diameter sewer, the gradient required to generate self-cleaning velocity is A. 1 in 10 B. 1 in 100 C. 1 in 200 D. 1 in 300 12 / 25 12. Laying of sewer is generally done with the help of A. Sigh rail and boning rods B. Theodolite and staff C. Levelling and staff D. All of the above 13 / 25 13. The gases are given out of septic tank are A. CH4, oxygen and hydrogen B. CO2, H2S and methane C. CO2, PH3 and ammonia D. none of the above 14 / 25 14. The gas most commonly associated with septic waste water is A. CO B. CO2 C. CH4 D. H2S 15 / 25 15. A septic tank is a water tight tank where the following operation take pace A. Sedimentation B. Sedimentation + digestion (anaerobic) C. Digestion (aerobic) D. Decomposition of organic and inorganic matter by bacteria 16 / 25 16. Septic tank effluent is A. Quite clear and sparkling B. Always odorless C. Having fine organic solids with high bod D. Black tarry liquor with earthen odor 17 / 25 17. Baffle wall in septic tank is A. Short side wall B. Long side wall C. Honey comb interior wall D. None of the above 18 / 25 18. Septic tank is provided for A. To eliminate the sewer system B. Tank for sedimentation cum disposal under aerobic condition C. Oxygen free sedimentation cum disposal under anaerobic condition D. None of above 19 / 25 19. The digested sludge from septic tanks, is removed after a maximum period of A. 3 years B. 3.5 years C. 4 years D. 5 years 20 / 25 20. The detention time in a septic tank is usually A. 1-2 hours B. 5-6 hours C. 22- 24 hours D. 6-8 hours 21 / 25 21. From septic tank the effluents are discharged into A. Drainage B. Soak pit C. Sewer D. None 22 / 25 22. In septic tanks, decomposition of organic bacteria, is done by A. Anaerobic bacteria B. Aerobic bacteria C. Both type of bacteria D. None 23 / 25 23. The length of septic tank is …………. times of its width A. 2 to 3 B. 2 to 4 C. 2 to 5 D. 2 to 6 24 / 25 24. What is the shape of septic tank A. Rectangle B. Square C. Circular D. Oval 25 / 25 25. Septic tank is best suited for A. Municipalities B. Industries C. Scattered residences D. Congested areas Your score is The average score is 56% 0% Restart quiz Exit civil engineernecpscupscWater Supply & Sanitation
