Mechanical Operations — Part 2 MCQs with Explanations

Cage is the correct answer to “__________ mill is not a revolving mill.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Cage mill is the correct answer to “Which of the following is not a revolving/tumbling mill used for size reduction”. This question is standard in competitive examination syllabi for Mechanical Operations.

Suspended batch basket is the correct answer to “__________ centrifuge is normally used in sugar mills.”. This question is standard in competitive examination syllabi for Mechanical Operations.

HGI is the correct answer to “Grinding characteristic of a material is given by its”. This question is standard in competitive examination syllabi for Mechanical Operations.

Froth floatation is the correct answer to “Which of the following is the most suitable for cleaning of fine coal dust (<0.5 mm)”. This question is standard in competitive examination syllabi for Mechanical Operations.

Sharpies supercentrifuge is the correct answer to “Which of the following can be most effectively used for clarification of lube oil and printing ink”. This question is standard in competitive examination syllabi for Mechanical Operations.

0.087 L.S is the correct answer to “Capacity (in tons/hr) of jaw/gyratory crusher is equal to (where, L = length of the receiving opening, cm S = greater width of the discharge opening, cm)”. This question is standard in competitive examination syllabi for Mechanical Operations.

$$\sqrt 2 $$ is the correct answer to “The ratio of the actual mesh dimension of Taylor series to that of the next smaller screen is”. This question is standard in competitive examination syllabi for Mechanical Operations.

Ratio of surface to volume as the actual volume is the correct answer to “Equivalent diameter of a particle is the diameter of the sphere having the same”. This question is standard in competitive examination syllabi for Mechanical Operations.

1.34 Wi is the correct answer to “The value of work index does not change materially from one equipment to another. If the value of work index determined for close circuit grinding is Wi, then the same for open circuit grinding will be”. This question is standard in competitive examination syllabi for Mechanical Operations.

1000°C and 10 atm is the correct answer to “Dust collection efficiency of electrostatic precipitator can be as high as 99.9%. Maximum temperature and pressure of dust laden gas that can be cleaned in an electrostatic precipitator is respectively.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Cobalt oxide is the correct answer to “Which of the following oxides is not present in hematite iron ore”. This question is standard in competitive examination syllabi for Mechanical Operations.

Rod mill is the correct answer to “Which of the following grinding mills has the horizontally arranged rods as the grinding elements thereby delivering more uniform granular products with minimum fines”. This question is standard in competitive examination syllabi for Mechanical Operations.

None of these is the correct answer to “Filtration rate does not depend upon the”. This question is standard in competitive examination syllabi for Mechanical Operations.

Compression is the correct answer to “For coarse reduction of hard solids, use”. This question is standard in competitive examination syllabi for Mechanical Operations.

Inch is the correct answer to “200 mesh screen means 200 openings per”. This question is standard in competitive examination syllabi for Mechanical Operations.

Either A, B or C is the correct answer to “Vibrating screens are used for handling large tonnages of materials. The vibrating motion is imparted to the screening surface by means of”. This question is standard in competitive examination syllabi for Mechanical Operations.

Buhrstone mill is the correct answer to “For grinding of cereals, grains, spices, pigments, saw dust, cork etc., the most extensively used size reduction equipment is a”. This question is standard in competitive examination syllabi for Mechanical Operations.

32° is the correct answer to “What is the usual value of angle of nip for crushing of ordinary rock in smooth steel crushing rolls”. This question is standard in competitive examination syllabi for Mechanical Operations.

Volume-surface is the correct answer to “Sauter mean diameter is the same as the __________ mean diameter.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Early stages is the correct answer to “Filter medium resistance is important during the __________ of filtration.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Density is the correct answer to “Power consumption during turbulent flow in agitation tank is proportional to the __________ of the liquid.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Both B and C is the correct answer to “Mechanical conveyors which push the material along an endless trough or tube are called scrappers. Which of the following conveying equipments comes under the category of 'scrappers'”. This question is standard in competitive examination syllabi for Mechanical Operations.

Kozney-Karman equation is the correct answer to “For laminar flow of filtrate through the cake deposited on septum, which of the following will be valid”. This question is standard in competitive examination syllabi for Mechanical Operations.

Frother is the correct answer to “Pine oil and cresylic acid are used as __________ in the froth floatation process.”. This question is standard in competitive examination syllabi for Mechanical Operations.

$$\frac{1}{4}$$ is the correct answer to “In washing type plate and frame filter press, the ratio of washing rate to the final filtrate rate is”. This question is standard in competitive examination syllabi for Mechanical Operations.

Either A or B is the correct answer to “Specific surface area is the surface area of a unit __________ of materials.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Ultrafine is the correct answer to “Colloidal mills are used for __________ grinding.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Solids from fluids is the correct answer to “Cyclones are used primarily for separating”. This question is standard in competitive examination syllabi for Mechanical Operations.

π(=A/D²) is the correct answer to “For spheres, the surface shape factor is given by (where, A = area, V = volume, and D = diameter)”. This question is standard in competitive examination syllabi for Mechanical Operations.

Np ∝ $$\frac{1}{{{{\text{N}}_{{\text{Re}}}}}}$$ is the correct answer to “For a turbine agitated and baffled tank, operating at low Reynold's number (based on impeller diameter), the power number (N p ) varies with N Re as”. This question is standard in competitive examination syllabi for Mechanical Operations.

Independent of ΔP is the correct answer to “The specific cake resistance for incompressible sludges is (where ΔP = pressure drop over cake)”. This question is standard in competitive examination syllabi for Mechanical Operations.

D is the correct answer to “Height of liquid in agitation tank is normally maintained equal to the tank diameter. However, if the tank is too tall and a large liquid hold up is desired, then two or more impellers mounted on the same shaft may be used. The clearance between the tank bottom and the bottom most impeller should be about (where, D = impeller diameter)”. This question is standard in competitive examination syllabi for Mechanical Operations.

$${\text{N}} \propto \frac{1}{{\sqrt {\text{D}} }}$$ is the correct answer to “The critical speed of a trommel (N) is related to its dia (D) as”. This question is standard in competitive examination syllabi for Mechanical Operations.

Bulk of the solids are removed at the periphery of the disks is the correct answer to “Cartridge filters are termed as 'edge' filters, because of the fact that the”. This question is standard in competitive examination syllabi for Mechanical Operations.

Terminal velocities in the same fluid & in the same field of force is the correct answer to “Two particles are called to be equal settling, if they are having the same.”. This question is standard in competitive examination syllabi for Mechanical Operations.

Centrifugation is the correct answer to “If a force greater than that of gravity is used to separate solids & fluids of different densities, the process is termed as the”. This question is standard in competitive examination syllabi for Mechanical Operations.

3.6 AVS.ρ is the correct answer to “The capacity of a classifier in 'tons of solid/hr' is given by (where, A = cross-sectional area, m 2 , V = rising velocity of fluid, m/sec, S = percentage of solids in the suspension by volume, ρ = density of solids, kg/m 3 )”. This question is standard in competitive examination syllabi for Mechanical Operations.

$$\frac{1}{{{{\text{D}}_{\text{p}}}}}$$ is the correct answer to “The specific surface of sherical particles is proportional to (where, D p = diameter of particle).”. This question is standard in competitive examination syllabi for Mechanical Operations.

Increases capacity is the correct answer to “Wet grinding in a revolving mill __________ as compared to dry grinding.”. This question is standard in competitive examination syllabi for Mechanical Operations.