In primary sedimentation, the 0.2 mm inorganic solids get separated if specific gravity is_________________?

Related Mcqs:

1. A sewer pipe contains 1 mm sand particles of specific gravity 2.65 and 5 mm organic particles of specific gravity 1.2, the minimum velocity required for removing the sewerage, is_____________________?

   A. 0.30 m/sec
   B. 0.35 m/sec
   C. 0.40 m/sec
   D. 0.45 m/sec

2. A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction of it volume is under mercury ?

   A. the metal piece will simply float over the mercury
   B. the metal piece will be immersed in mercury by half
   C. whole of the metal piece will be immersed with its top surface just at mercury level
   D. metal piece will sink to the bottom
   E. none of the above

3. A metal with specific gravity of o floating in a fluid of same specific gravity a will___________________?

   A. sink to bottom
   B. float over fluid
   C. partly immersed
   D. be fully immersed with top surface at fluid surface
   E. none of the above

4. A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6. What fraction of its volume is under mercury ?

   A. 0.5
   B. 0.4
   C. 0.515
   D. 0.5
   E. none of the above

5. The normal value of over flow rates for plain primary sedimentation tanks, ranges between________________?

   A. 25,000 to 35,000 litres/sqm/day
   B. 40,000 to 50,000 litres/sqm/day
   C. 50,000 to 60,000 litres/sqm/day
   D. 80,000 to 100,000 litres/sqm/day

6. The settlement velocity of a solid (diameter 0.5 mm, specific gravity 1.75) in water having temperature 10°C, is______________________?

   A. 213.5 cm/sec
   B. 313.5 cm/sec
   C. 413.5 cm/sec
   D. 500 cm/sec

7. An odd shaped body weighing 7.5 kg and occupying 0.01 m3 volume will be completely submerged in a fluid having specific gravity of_________________?

   A. 1
   B. 1.2
   C. 0.8
   D. 0.75
   E. 1.25

8. A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specific gravity is__________________?

   A. 1
   B. 5
   C. 7
   D. 6

9. A piece of wood having weight 5 kg floats in water with 60% of its volume under the liquid. The specific gravity of wood is__________________?

   A. 0.83
   B. 0.6
   C. 0.4
   D. 0.3
   E. none of the above

10. The normal values of over flow rates for sedimentation tanks using coagulant, ranges between__________________?

    A. 25,000 to 35,000 litres/sqm/day
    B. 40,000 to 50,000 litres/sqm/day
    C. 50,000 to 60,000 litres/sqm/day
    D. 80,000 to 100,000 litres/sqm/day