MCQOPTIONS
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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.
| 301. |
Refractory bricks with lower permeability is produced by using |
| A. | higher firing temperature. |
| B. | higher moulding pressure. |
| C. | finer grog size. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 302. |
Orlan fibre which is used as a wool sub stitute is |
| A. | an amorphous polymer. |
| B. | a natural polymeric fibre. |
| C. | polyacrylonitrile. |
| D. | polymethylmethacrylate (PMMA). |
| Answer» D. polymethylmethacrylate (PMMA). | |
| 303. |
Starting material for the production of SBR is |
| A. | ethyl alcohol |
| B. | ethylene |
| C. | both (a) & (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 304. |
Density of high density polythene is about __________ gm/c.c. |
| A. | 1.18 |
| B. | 1.05 |
| C. | 0.95 |
| D. | 0.99 |
| Answer» D. 0.99 | |
| 305. |
Thiokol is nothing but |
| A. | polysulphide rubber |
| B. | polyamide fibre |
| C. | engineering plastic |
| D. | exponded polystyrene |
| Answer» B. polyamide fibre | |
| 306. |
Styrene butadiene rubber (SBR) as compared to natural rubber has |
| A. | poor tensile strength. |
| B. | poorer resistance. |
| C. | greater amount of heat build up heavy loading. |
| D. | all (a), (b) ana (c). |
| Answer» E. | |
| 307. |
Which of the following polymers has the tendency of decomposing before melting ? |
| A. | Polystyrene |
| B. | Nylon |
| C. | PVC |
| D. | None of these |
| Answer» D. None of these | |
| 308. |
Vinyl flooring is done using __________ sheets. |
| A. | polypropylene |
| B. | PVC |
| C. | polythene |
| D. | polyvinyl acetate |
| Answer» C. polythene | |
| 309. |
Which of the following polymers belong to the class of formaldehyde resin ? |
| A. | Melamine resins |
| B. | Teflon |
| C. | Dacron |
| D. | None of these |
| Answer» B. Teflon | |
| 310. |
Trade name of __________ is neoprene. |
| A. | polychloroprene |
| B. | polyisoprene |
| C. | polytetraflouroethylene |
| D. | poly vinyl acetate |
| Answer» B. polyisoprene | |
| 311. |
SBR is produced by the copolymerisation of butadiene & styrene by employing emulsion polymerisation. The weight ratio of styrene and butadiene is maintained at |
| A. | 1:3 |
| B. | 3:1 |
| C. | 1:2 |
| D. | 2:1 |
| Answer» B. 3:1 | |
| 312. |
Transistor parts and refrigerator components are normally made of |
| A. | polystyrene |
| B. | polyester |
| C. | high density polythene |
| D. | polyurathane |
| Answer» B. polyester | |
| 313. |
Fillers such as zinc oxide and carbon black are added to the crude natural rubber before vulcanisation in order to improve its |
| A. | elasticity |
| B. | strength |
| C. | plasticity |
| D. | weathering characteristics |
| Answer» E. | |
| 314. |
The organic acid monomer in nylon 66 is |
| A. | sebasic acid |
| B. | terephthalic acid |
| C. | adipic acid |
| D. | benzoic acid |
| Answer» D. benzoic acid | |
| 315. |
Neoprene which is used for making shoe heels & belts is superior to natural rubber in its stability to aerial oxidation and resistance to oils & other solvents. The monomer used for making neoprene is |
| A. | chloroethane |
| B. | chlorophrene |
| C. | isoprene |
| D. | none of these |
| Answer» C. isoprene | |
| 316. |
Dacron (or terylene) fibres as compared to nylon fibres have |
| A. | better heat & acid resistant properties. |
| B. | poorer resistance to alkalis. |
| C. | poorer dyeability. |
| D. | all (a), (b) and (c). |
| Answer» E. | |
| 317. |
Which of the following low molecular weight (<104 ), soft & waxy polymer is used in chewing gum ? |
| A. | Cellulose acetate |
| B. | Polyvinyl acetate |
| C. | Thiokol |
| D. | PVC |
| Answer» C. Thiokol | |
| 318. |
The main use of butadiene is |
| A. | as a plasticiser for unsaturated polyester. |
| B. | in the manufacture of synthetic rubber. |
| C. | as an anti-skimming agent in paint. |
| D. | none of these. |
| Answer» C. as an anti-skimming agent in paint. | |
| 319. |
Mastication of rubber means |
| A. | its softening. |
| B. | a treatment to retard its deterioration due to oxidation. |
| C. | improving its curing rate. |
| D. | depression of its freezing point. |
| Answer» B. a treatment to retard its deterioration due to oxidation. | |
| 320. |
Reaction of dimethyl terephthalate (DMT) and ethylene glycol produces |
| A. | nylon-6 |
| B. | dacron |
| C. | polyester |
| D. | PVC |
| Answer» C. polyester | |
| 321. |
Tubeless tyres are made of __________ rubber, which is a co-polymer of isoprene & isobutylene. |
| A. | nitrile |
| B. | silicone |
| C. | neoprene |
| D. | butyl |
| Answer» E. | |
| 322. |
Zeigler - Natta catalyst (AlR3 - AlCl3) is used in the polymerisation of |
| A. | vinyl acetate |
| B. | vinyl chloride |
| C. | propylene |
| D. | styrene |
| Answer» D. styrene | |
| 323. |
Due to its excellent permeability to air/gas and oxidation resistance, the tubes of automobile tyres is made of |
| A. | cold SBR |
| B. | butyl rubber |
| C. | Bunai N |
| D. | Buna S |
| Answer» C. Bunai N | |
| 324. |
90% of the caprolactum is converted to nylon-6 on its condensation polymerisation in the reactor maintained at a temperature of __________ C. |
| A. | -5 |
| B. | 10-30 |
| C. | 250-280 |
| D. | 500-600 |
| Answer» D. 500-600 | |
| 325. |
Out of all the elastomers, natural rubber has the longest elongation range & flexibility of the order of __________ percent. |
| A. | 1-1000 |
| B. | 1000-1500 |
| C. | 1500-2000 |
| D. | 2000-2500 |
| Answer» B. 1000-1500 | |
| 326. |
Hydrogen content of coke oven gas is __________ percent. |
| A. | 4 |
| B. | 22 |
| C. | 58 |
| D. | 84 |
| Answer» D. 84 | |
| 327. |
Ammonium nitrate (a fertiliser) is coated with limestone powder to |
| A. | increase its nitrogen content. |
| B. | cut down its production cost. |
| C. | avoid the risk of explosion. |
| D. | add extra nutrient as fertiliser. |
| Answer» D. add extra nutrient as fertiliser. | |
| 328. |
Si percentage in silica refractories used in the walls of coke oven is about |
| A. | 45 |
| B. | 60 |
| C. | 80 |
| D. | 95 |
| Answer» E. | |
| 329. |
Silica bricks are attacked by basic slags at high temperature. Which of the following is not used solely as a binding material? |
| A. | aluminium phosphate |
| B. | water |
| C. | lime |
| D. | plaster of paris |
| Answer» C. lime | |
| 330. |
Cold crushing strength of refractories depends upon its |
| A. | composition |
| B. | texture |
| C. | firing temperature |
| D. | all (a), (b) and (c) |
| Answer» E. | |
| 331. |
High thermal conductivity of a refractory material is not important, when it is to be used in the |
| A. | coke oven regenarators |
| B. | muffle furnace |
| C. | blast furnace |
| D. | recuperators |
| Answer» D. recuperators | |
| 332. |
Maximum safe working temperature for fireclay bricks is about __________ C. |
| A. | 1150 |
| B. | 1300 |
| C. | 1450 |
| D. | 1550 |
| Answer» E. | |
| 333. |
Which is not an alumino-silicate refractory? |
| A. | Fireclay bricks. |
| B. | Mullite bricks. |
| C. | Tar dolomite bricks. |
| D. | High alumina bricks. |
| Answer» D. High alumina bricks. | |
| 334. |
Permeability of bricks is a measure of the |
| A. | refractoriness. |
| B. | melting point. |
| C. | rate at which a fluid will pass through the pores. |
| D. | expansion during heating. |
| Answer» D. expansion during heating. | |
| 335. |
With increase in the density of silica refractories, its |
| A. | resistance to slag attack increases. |
| B. | spalling resistance reduces. |
| C. | both (a) and (b). |
| D. | neither (a) nor (b). |
| Answer» D. neither (a) nor (b). | |
| 336. |
Electrical resistor bars are made of |
| A. | silicon carbide |
| B. | alumina |
| C. | zirconia |
| D. | graphite |
| Answer» B. alumina | |
| 337. |
PCE value (Segar cone) of superduty refractories is more than 33, which is equivalent to a temperature of __________ C. |
| A. | 1520 |
| B. | 1630 |
| C. | 1670 |
| D. | 1730 |
| Answer» E. | |
| 338. |
Addition of zircon to silica refractory brick improves its |
| A. | crushing strength |
| B. | resistance to slag attack |
| C. | both (a) and (b) |
| D. | neither (a) nor (b) |
| Answer» C. both (a) and (b) | |
| 339. |
Thermal spalling mainly occurs during __________ of furnaces. |
| A. | cooling down |
| B. | warming up |
| C. | both (a) & (b) |
| D. | neither (a) nor (b) |
| Answer» D. neither (a) nor (b) | |
| 340. |
Pure bauxite is the best raw material for the manufacture of high alumina refractories, in which maximum alumina content can be as high as __________ percent. |
| A. | 55 |
| B. | 70 |
| C. | 80 |
| D. | 90 |
| Answer» E. | |
| 341. |
Which of the following is not an acidic refractory ? |
| A. | Silica bricks |
| B. | Fireclay bricks |
| C. | Bauxite bricks |
| D. | Magnesia bricks |
| Answer» E. | |
| 342. |
Insulating refractories should have |
| A. | high porosity |
| B. | low thermal conductivity |
| C. | both (a) and (b) |
| D. | neither (a) not (b) |
| Answer» C. both (a) and (b) | |
| 343. |
Fireclay bricks is not used for lining the |
| A. | cupola. |
| B. | gas producer. |
| C. | bottom of hot metal mixer. |
| D. | roof of open hearth furnace. |
| Answer» D. roof of open hearth furnace. | |
| 344. |
Refractoriness under loads (RUL) is quite close to the fusion temperature (PCE) for __________ bricks. |
| A. | fireclay |
| B. | silica |
| C. | dolomite |
| D. | very low alumina |
| Answer» C. dolomite | |
| 345. |
Tar bonded dolomite bricks |
| A. | are stored under controlled temperature & humidity to avoid hydration. |
| B. | are used in outer lining of L.D. converters. |
| C. | have poorer hydration resistance than pitch bonded bricks. |
| D. | all (a), (b) and (c) |
| Answer» E. | |
| 346. |
Which is the most stable crystalline form of silica at room temperature ? |
| A. | Quartz |
| B. | Cristobalite |
| C. | Tridymite |
| D. | None of these |
| Answer» B. Cristobalite | |
| 347. |
Silica refractories |
| A. | crack when subjected to sudden change of temperature. |
| B. | can not be used in the dome of hot blast stoves. |
| C. | have lower thermal conductivity than fireclay bricks. |
| D. | all (a), (b) and (c) |
| Answer» B. can not be used in the dome of hot blast stoves. | |
| 348. |
Action of phosphoric acid on rock phosphate produces |
| A. | superphosphate |
| B. | triple superphosphate |
| C. | nitrophosphate |
| D. | diammonium phosphate |
| Answer» C. nitrophosphate | |
| 349. |
Red phosphorous is changed into white phosphorous by |
| A. | heating in presence of light. |
| B. | melting under pressure. |
| C. | vaporisation followed by condensation. |
| D. | none of these. |
| Answer» D. none of these. | |
| 350. |
Two gas based fertiliser plants are located in |
| A. | Maharashtra and Gujarat |
| B. | Maharashtra and Orissa |
| C. | Gujarat and Madhya Pradesh |
| D. | Jharkhand and Chattisgarh |
| Answer» B. Maharashtra and Orissa | |