Gravity settling process is not involved in the working of a________________?

Related Mcqs:

1. A suspension of glass beads in ethylene glycol has a hindered settling velocity of 1.7 mm/s, while the terminal settling velocity of a single glass bead in ethylene glycol is 17 mm/s. If the Richardson-Zaki hindered settling index is 4.5, the volume fraction of solids in the suspension is_____________?

   A. 0.1
   B. 0.4
   C. 0.6
   D. None of these

2. A 30% (by volume) suspension of spherical sand particles in a viscous oil has a hindered settling velocity of 4.44 μm/s. If the Richardson Zaki hindered settling index is 4.5, then the terminal velocity of a sand grain is_________________?

   A. 0.90 μm/s
   B. 1 μm/s
   C. 22.1 μm/s
   D. 0.02 μm/s

3. Particle size range in which dust catcher (gravity settling chamber) works most effectively and efficiently is ______________ microns?

   A. < 5
   B. 10 to 25
   C. < 74
   D. > 1000

4. In classification, particles are said to be equal settling, if they have the same terminal velocities in the_______________?

   A. Different fluids
   B. Same fluid
   C. Same field of force
   D. Both B. and C.

5. Two particles are called to be equal settling, if they are having the same ?

   A. Size
   B. Specific gravity
   C. Terminal velocities in the same fluid & in the same field of force
   D. None of these

6. Sorting classifiers employing differential settling methods for separation of particles make use of the differences in their_________________?

   A. Particle sizes
   B. Densities
   C. Terminal velocities
   D. None of these

7. If a force greater than that of gravity is used to separate solids & fluids of different densities, the process is termed as the __________________?

   A. Sedimentation
   B. Flocculation
   C. Dispersion
   D. Centrifugation

8. Critical speed of rotation, N (in rps – rotation per second) of a trammel is equal to (where, g = acceleration due to gravity = 9.81 m/sec2 and, r = radius of trammel, metre.) ?

   A. (1/2π). √(g/r)
   B. (1/π). √(g/r)
   C. ½ √(g/r)
   D. 2π. √(g/r)

9. Gravity stamp mill is meant for the ___________________ crushing?

   A. Primary
   B. Intermediate
   C. Fine
   D. Ultrafine

10. The important dimensional group involved in the power requirement calculation in mixing operation is the _____________ number?

    A. Reynold’s
    B. Froude
    C. Both A. & B.
    D. Neither A. nor B.