Mechanical Operations Questions

• Production rate __________ with increased fineness, with a given energy input to the size reduction machine.
• The unit of specific cake resistance is
• Ultra centrifuges are used for the separation of __________ solid particles.
• 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).
• Gold ore concentration is mostly done using
• 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.
• Out of the following size reduction equipments, the maximum feed size can be accepted by the
• 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?
• Electrical energy consumed by a jaw crusher is not a function of the
• Which of the following gives the work required for size reduction of coal to -200 mesh in a ball mill most accurately?
• Which of the following represents the plot of filtrate volume versus time for constant pressure filtration?
• For removal of very small amounts of precipitate from large volume of water, the most suitable filter is the __________ filter.
• Mesh indicates the number of holes per
• Colloid mills achieve size reduction mainly by
• A pebble mill
• Moisture can be removed from lubricating oil using
• The most common filter aid is
• Size reduction of asbestos and mica is done by
• For achieving maximum capacity of the ball mill, the ball charge should be equal to about __________ percent of the ball mill volume.
• The speed of a rotary drum vacuum filter may be about __________ rpm.