In a sedimentation tank (length L, width B, depth D) the settling velocity of a particle for a discharge Q, is____________________?

Related Mcqs:

1. The settling velocity of the particles larger than 0.06 mm in a settling tank of depth 2.4 is 0.33 m per sec. The detention period recommended for the tank, is____________________?

   A. 30 minutes
   B. 1 hour
   C. 1 hour and 30 minutes
   D. 2 hours

2. The sewage discharge in a detritus tank of a treatment plant is 576 litres/sec with flow velocity of 0.2 m/sec. If the ratio of width to depth is 2, the depth is____________________?

   A. 100 cm
   B. 110 cm
   C. 120 cm
   D. 150 cm

3. The dimensions of a rectangular settling tank are: length 24 m, width 6 m and depth 3 m. If 2 hour detention period for tanks is recommended, the rate of flow of sewage per hour, is_____________________?

   A. 204 cu.m
   B. 208 cu.m
   C. 212 cu.m
   D. 216 cu.m

4. The width of a settling tank with 2 hour detention period for treating sewage 378 cu m per hour, is __________________?

   A. 5 m
   B. 5.5 m
   C. 6.5 m
   D. 7 m

5. The settlement of a particle in sedimentation tank, is affected by_____________________?

   A. Velocity of flow
   B. Viscosity of water
   C. Size and shape of solid
   D. All the above

6. The ratio of design discharge to the surface area of a sedimentation tank is called____________________?

   A. Surface loading
   B. Overflow rate
   C. Overflow velocity
   D. All of these

7. The discharge per unit plan area of a sedimentation tank, is generally called________________?

   A. Over flow rate
   B. Surface loading
   C. Over flow velocity
   D. All the above

8. The settling velocity of a spherical particle of diameter less than 0.1 mm as per Stock’s law, is__________________?

   A. Vs = 418 (Gs – Gw) d [(3T + 70)/100]
   B. Vs = 418 (Gs – Gw)d² [(3T + 70)/100]
   C. Vs = 218 (Gs – Gw)d² [(3T + 70)/100]
   D. Vs = 218 (Gs – Gw)d [(3T + 70)/100]

9. The width of a rectangular sewer is twice its depth while discharging 1.5 m/sec. The width of the sewer is______________?

   A. 0.68 m
   B. 0.88 m
   C. 1.36 m
   D. 1.76 m

10. The detention time (t) of a settling tank, may be defined as the time required for_________________?

    A. A particle to travel along its length
    B. A particle to travel from top surface to bottom sludge zone
    C. The flow of sewage to fill the tank
    D. None of these