logo

CuriousTab

CuriousTab

Discussion


Home Chemical Engineering Mechanical Operations Comments

  • Question
  • Ultra centrifuges are used for the separation of __________ solid particles.


  • Options
  • A. coarse
  • B. fine
  • C. colloidal
  • D. dissolved

  • Correct Answer
  • colloidal 


  • Mechanical Operations problems


    Search Results


    • 1. The unit of specific cake resistance is

    • Options
    • A. gm/cm2
    • B. cm/gm
    • C. cm/gm2
    • D. gm/gm
    • Discuss
    • 2. Production rate __________ with increased fineness, with a given energy input to the size reduction machine.

    • Options
    • A. decreases
    • B. increases
    • C. remains unchanged
    • D. may increase or decrease; depends on the machine
    • Discuss
    • 3. The specific cake resistance for compressible sludges is a function of the pressure drop

    • Options
    • A. over cake
    • B. over medium
    • C. overall
    • D. none of these
    • Discuss
    • 4. Size reduction does not occur due to compression in case of

    • Options
    • A. rod mills
    • B. gyratory crushers
    • C. jaw crushers
    • D. smooth roll crushers
    • Discuss
    • 5. Mixing of light fine powder such as insecticides is done by

    • Options
    • A. banbery mixer
    • B. pug mill
    • C. impact wheels
    • D. kneader
    • Discuss
    • 6. According to Bond crushing law, the work required to form particle of size 'D' from very large feed is (where (S/V)p and (S/V)f are surface to volume ratio of the product and feed respectively).

    • Options
    • A. (S/V)p
    • B. (S/V)p
    • C. (S/V)2p
    • D. (S/V)f
    • Discuss
    • 7. Gold ore concentration is mostly done using

    • Options
    • A. jigging
    • B. tabling
    • C. froth floatation
    • D. elutriation
    • Discuss
    • 8. Pulverised coal passing through 200 mesh screen has a diameter of 0.074 mm (74 micron). The same passing through 50 mesh screen will have a dia of __________ mm.

    • Options
    • A. 0.007
    • B. 0.30
    • C. 50
    • D. 0.014
    • Discuss
    • 9. Out of the following size reduction equipments, the maximum feed size can be accepted by the

    • Options
    • A. tube mill
    • B. ball mill
    • C. jaw crusher
    • D. jet pulveriser
    • Discuss
    • 10. Sphericity is the ratio of the surface area of a spherical particle having the same volume as the particle to the surface area of the particle. Which of the following has the maximum value of sphericity?

    • Options
    • A. Sphere
    • B. Cube
    • C. Cylinder (L/D = 1)
    • D. Raschig rings
    • Discuss


    Comments

    There are no comments.

Enter a new Comment