Crushing of mineral particles is accomplished in a ‘cage mill’, when one or more alloy steel bars are revolved in opposite directions. It is a type of ______________ mill?

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

A. Surface energy created by crushing to the energy absorbed by the solid
B. Energy absorbed by the solid to that fed to the machine
C. Energy fed to the machine to the surface energy created by crushing
D. Energy absorbed by the solid to the surface energy created by crushing

A. Work required to form a particle of any size is proportional to the square of the surface to
volume ratio of the product
B. Work required to form a particle of a particular size is proportional to the square root of the
surface to volume ratio of the product
C. Work required in crushing is proportional to the new surface created
D. For a given machine and feed, crushing efficiency is dependent on the size of the feed &
product

A. Increases
B. Decreases
C. Remain constant
D. May increase or decrease; depends on the material being ground

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

A. 0.01 to 0.1
B. 0.5 to 1.5
C. 2 to 3.5
D. 4 to 5