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MCQOPTIONS
This section includes 8247 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 6251. |
According to Taggart's rule for selecting between a gyratory crusher and a jaw crusher; the later should be used, if the hourly tonnage to be crushed divided by the square of the gape expressed in cm is less than |
| A. | 0.00184 |
| B. | 0.0184 |
| C. | 0.184 |
| D. | 1.84 |
| Answer» C. 0.184 | |
| 6252. |
Electrical energy consumed by a jaw crusher is not a function of the |
| A. | average feed size |
| B. | average product size |
| C. | machine capacity |
| D. | none of these |
| Answer» E. | |
| 6253. |
Which of the following represents the plot of filtrate volume versus time for constant pressure filtration ? |
| A. | Parabola |
| B. | Straight line |
| C. | Hyperbola |
| D. | Exponential curve |
| Answer» B. Straight line | |
| 6254. |
Driving force in case of filtration by a centrifuge is the |
| A. | speed of the centrifuge. |
| B. | centrifugal pressure exerted by the liquid. |
| C. | narrow diameter of the vessel. |
| D. | formation of highly porous cake. |
| Answer» C. narrow diameter of the vessel. | |
| 6255. |
Size reduction mechanism used in Jaw crushers is |
| A. | attrition |
| B. | compression |
| C. | cutting |
| D. | impact |
| Answer» C. cutting | |
| 6256. |
Trommels employ __________ for screening of materials. |
| A. | fibrous cloth |
| B. | woven wire screen |
| C. | punched plate |
| D. | none of these |
| Answer» D. none of these | |
| 6257. |
Ultra centrifuges are used for the separation of __________ solid particles. |
| A. | coarse |
| B. | fine |
| C. | colloidal |
| D. | dissolved |
| Answer» D. dissolved | |
| 6258. |
A widely used size reduction equipment for __________ is Bradford breaker. |
| A. | talc |
| B. | coal |
| C. | iron core |
| D. | wheat |
| Answer» C. iron core | |
| 6259. |
-rays are |
| A. | negatively charged. |
| B. | positively charged. |
| C. | neutral. |
| D. | same as X-rays. |
| Answer» C. neutral. | |
| 6260. |
Which of the following terminology is not used for size reduction of materials to fine sizes or powders? |
| A. | Comminution |
| B. | Dispersion |
| C. | Pulverisation |
| D. | Compression |
| Answer» E. | |
| 6261. |
Specific surface area is the surface area of a unit __________ of materials. |
| A. | weight |
| B. | volume |
| C. | either (a) or (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 6262. |
A. __________ mill is a revolving mill divided into two or more sections by perforated partitions in which preliminary grinding takes place at one end and the finishing grinding at the discharge end. |
| A. | compartment |
| B. | tube |
| C. | rod |
| D. | pebble. |
| Answer» B. tube | |
| 6263. |
The constants (Kb, Kr and Kk) used in the laws of crushing (i.e., Bond's law, Rittinger's law and Kick's law) depend upon the |
| A. | feed material. |
| B. | type of crushing machine. |
| C. | both (a) & (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 6264. |
A pebble mill |
| A. | is a ball mill. |
| B. | employs flints or ceramic pebbles as the grinding medium. |
| C. | is a tube mill lined with ceramic or other non-metallic liner. |
| D. | both (b) and (c). |
| Answer» E. | |
| 6265. |
The study on washability of coal is done by using the __________ technique. |
| A. | tabling |
| B. | elutriation |
| C. | heavy media separation |
| D. | none of these |
| Answer» D. none of these | |
| 6266. |
Horsepower required for a roll crusher is directly proportional to its |
| A. | reduction ratio. |
| B. | capacity. |
| C. | both (a) & (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 6267. |
Production rate __________ with increased fineness, with a given energy input to the size reduction machine. |
| A. | decreases |
| B. | increases |
| C. | remains unchanged |
| D. | may increase or decrease; depends on the machine |
| Answer» B. increases | |
| 6268. |
Gold ore concentration is mostly done using |
| A. | jigging |
| B. | tabling |
| C. | froth floatation |
| D. | elutriation |
| Answer» C. froth floatation | |
| 6269. |
Run of mine (ROM) coal is crushed by a __________ for use in domestic ovens. |
| A. | jaw crusher |
| B. | hammer crusher |
| C. | ball mill |
| D. | tube mill |
| Answer» C. ball mill | |
| 6270. |
A tube mill as compared to a ball mill |
| A. | employs smaller balls. |
| B. | gives finer size reduction but consumes more power. |
| C. | has larger length/diameter ratio (>2 as compared to 1 for ball mill). |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 6271. |
Kick's law assumes that the energy required for size reduction is proportional to the logarithm of the ratio between the initial and the final diameters. The unit of Kick's constant is |
| A. | kW. sec/kg |
| B. | kWh/kg |
| C. | kWh/sec. kg |
| D. | kg/sec. |
| Answer» B. kWh/kg | |
| 6272. |
A suspension of glass beads in ethylene glycol has a hindered settling velocity of 1.7 mm/s, while the terminal settling velocity of a single glass bead in ethylene glycol is 17 mm/s. If the Richardson-Zaki hindered settling index is 4.5, the volume fraction of solids in the suspension is |
| A. | 0.1 |
| B. | 0.4 |
| C. | 0.6 |
| D. | none of these |
| Answer» D. none of these | |
| 6273. |
The specific cake resistance for compressible sludges is a function of the pressure drop |
| A. | over cake |
| B. | over medium |
| C. | overall |
| D. | none of these |
| Answer» B. over medium | |
| 6274. |
Moisture can be removed from lubricating oil using |
| A. | tubular centrifuge |
| B. | clarifier |
| C. | sparkler filter |
| D. | vacuum leaf filter |
| Answer» B. clarifier | |
| 6275. |
Tabling process used for separating two materials of different densities by passing the dilute pulp over a table/deck, which is inclined from the horizontal surface at an angle of about |
| A. | 1 to 2 |
| B. | 2 to 5 |
| C. | 5 to 10 |
| D. | 10 to 15 |
| Answer» C. 5 to 10 | |
| 6276. |
General crushing equation is given by . Bond's crushing law isobtained by solving this equation for n = __________ and feed of infinite size. |
| A. | 1 |
| B. | 1.5 |
| C. | 2 |
| D. | 2.5 |
| Answer» C. 2 | |
| 6277. |
Which of the follwoing mechanical conveyors does not come under the division 'scrapers' ? |
| A. | Ribbon conveyor |
| B. | Flight conveyor |
| C. | Bucket elevators |
| D. | Drag conveyor. |
| Answer» D. Drag conveyor. | |
| 6278. |
Basic slag is not ground in |
| A. | jaw crushers |
| B. | ball mills |
| C. | compartment mills |
| D. | tube mills |
| Answer» B. ball mills | |
| 6279. |
Grindability of a material does not depend upon its |
| A. | elasticity |
| B. | hardness |
| C. | toughness |
| D. | size |
| Answer» E. | |
| 6280. |
Shape factor for a cylinder whose length equals its diameter is |
| A. | 1.5 |
| B. | 0.5 |
| C. | 1.0 |
| D. | 2.0 |
| Answer» B. 0.5 | |
| 6281. |
In case of a hammer crusher, the |
| A. | feed may be highly abrasive (Moh's scale >5). |
| B. | minimum product size is 3 mm. |
| C. | maximum feed size may be 50 mm. |
| D. | rotor shaft carrying hammers can be vertical or horizontal. |
| Answer» E. | |
| 6282. |
Dust laden air can be purified using a |
| A. | cyclone separator |
| B. | bag filter |
| C. | gravity settler |
| D. | tubular centrifuge |
| Answer» B. bag filter | |
| 6283. |
Filtration of water in a paper mill is done by a/an __________ filter. |
| A. | open sand |
| B. | plate and frame |
| C. | vacuum leaf |
| D. | sparkler |
| Answer» B. plate and frame | |
| 6284. |
Moore filter is a __________ filter. |
| A. | leaf |
| B. | press |
| C. | rotary |
| D. | sand |
| Answer» B. press | |
| 6285. |
Sphericity of a cubical particle, when its equivalent diameter is taken as the height of the cube, is |
| A. | 0.5 |
| B. | 1 |
| C. | <span class="root">2</span> |
| D. | <span class="root">3</span> |
| Answer» C. <span class="root">2</span> | |
| 6286. |
Ball mill is used for |
| A. | crushing |
| B. | coarse grinding |
| C. | fine grinding |
| D. | attrition |
| Answer» D. attrition | |
| 6287. |
In case of a ball mill, |
| A. | coarse feed requires a larger ball. |
| B. | fine feed requires a larger ball. |
| C. | operating speed should be more than the critical speed. |
| D. | none of these |
| Answer» B. fine feed requires a larger ball. | |
| 6288. |
The operating speed of a ball mill should be __________ the critical speed. |
| A. | less than |
| B. | much more than |
| C. | at least equal to |
| D. | slightly more than |
| Answer» B. much more than | |
| 6289. |
Use of baffles in agitators help in minimising the __________ tendency. |
| A. | swirling |
| B. | vortexing |
| C. | both (a) & (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 6290. |
__________ are used for the separation of coarse particles from a slurry of fine particles. |
| A. | Thickeners |
| B. | Classifiers |
| C. | Hydrocyclones |
| D. | Decanters |
| Answer» C. Hydrocyclones | |
| 6291. |
Fibrous material is broken by a |
| A. | rollcrusher |
| B. | squirrel-cage disintegrator |
| C. | ball mill |
| D. | tube mill |
| Answer» C. ball mill | |
| 6292. |
__________ is the most suitable for compounding rubber and plastic solids. |
| A. | Banbery mixer |
| B. | Pan mixer |
| C. | Pug mill |
| D. | Charge can mixer |
| Answer» B. Pan mixer | |
| 6293. |
Energy consumed for crushing one ton of material ranges from __________ kWh. |
| A. | 0.01 to 0.1 |
| B. | 0.5 to 1.5 |
| C. | 2 to 3.5 |
| D. | 4 to 5. |
| Answer» C. 2 to 3.5 | |
| 6294. |
For transporting pasty material, one will use a/an |
| A. | apron conveyor |
| B. | belt conveyor |
| C. | screw colaveyor |
| D. | bucket elevator |
| Answer» D. bucket elevator | |
| 6295. |
Where the density difference of the two liquid phase to be separated is very small (as in milk cream separator), the most suitable separator is a |
| A. | disc bowl centrifuge. |
| B. | sharpies supercentrifuge. |
| C. | batch basket centrifuge. |
| D. | sparkler filter. |
| Answer» B. sharpies supercentrifuge. | |
| 6296. |
A tube mill compared to a ball mill |
| A. | has a higher length/diameter ratio. |
| B. | produces a coarser product. |
| C. | has a higher diameter/length ratio. |
| D. | uses much larger balls. |
| Answer» B. produces a coarser product. | |
| 6297. |
Trommels separate a mixture of particles depending on their |
| A. | size |
| B. | density |
| C. | wettability |
| D. | electrical & magnetic properties |
| Answer» B. density | |
| 6298. |
Normal dosage of chlorine in public water supply scheme ranges from __________ ppm. |
| A. | 0.5 to 1 |
| B. | 10 to 15 |
| C. | 300 to 500 |
| D. | 1000 to 1500 |
| Answer» B. 10 to 15 | |
| 6299. |
The hardness of a grinding wheel is specified by the |
| A. | alphabetical letter. |
| B. | Rockwell hardness number. |
| C. | Brinell hardness number. |
| D. | none of these. |
| Answer» B. Rockwell hardness number. | |
| 6300. |
Mechanism/phenomenon involved in the improvement of fatigue strength of a material by shot peening is the |
| A. | induction of residual compressive stress on the surface. |
| B. | removal of stress concentration from the surface. |
| C. | grain refinement. |
| D. | surface polishing. |
| Answer» B. removal of stress concentration from the surface. | |