10 FEBRUARY 2021 CURRENT AFFAIRS QUIZ

__________ balls capable of grinding the feed in a ball mill gives the maximum efficiency.

Minimum size

Cast iron

Elliptical

Maximum size

TRUE ANSWER : ?
YOUR ANSWER : ?

Fluid energy mill comes in the category of

Grinder

Crusher

Ultrafine grinder

Cutter

TRUE ANSWER : ?
YOUR ANSWER : ?

Higher is the mesh number, smaller will be the aperture size of the screen. It means that the aperture size of a 200 mesh screen will be smaller than that of 20 mesh screen. This is valid for

British standard screens

German standard screens (DIN 1171) etc

American standard screens (ASTM and Tyler standard screens)

All of these

TRUE ANSWER : ?
YOUR ANSWER : ?

200 mesh screen means 200 openings per

Inch

Cm²

Inch²

Cm

TRUE ANSWER : ?
YOUR ANSWER : ?

Horsepower required for a roll crusher is directly proportional to its

Both A & B

Reduction ratio

Capacity

Neither A nor B

TRUE ANSWER : ?
YOUR ANSWER : ?

A pebble mill

Employs flints or ceramic pebbles as the grinding medium

Both B and C

Is a ball mill

Is a tube mill lined with ceramic or other non-metallic liner

TRUE ANSWER : ?
YOUR ANSWER : ?

Filtration capacity of a rotary drum vacuum filter depends upon the

Cake thickness

Both A & B

Neither A nor B

Characteristics of the feed slurry

TRUE ANSWER : ?
YOUR ANSWER : ?

For crushing of solids, the Rittinger's law states that the work required for crushing is proportional to

The size reduction ratio

None of these

The change in volume due to crushing

The new surface created

TRUE ANSWER : ?
YOUR ANSWER : ?

The specific surface of sherical particles is proportional to (where, Dp = diameter of particle).

1/Dp

1/D²p

D²p

Dp

TRUE ANSWER : ?
YOUR ANSWER : ?

Which is a secondary crusher for a hard & tough stone?

Cone crusher

Toothed roll crusher

Jaw crusher

Impact crusher

TRUE ANSWER : ?
YOUR ANSWER : ?