MCQOPTIONS
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MCQOPTIONS
This section includes 513 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 301. |
*/*_The specific fuel consumption per BH hour for a petrol engine is approximately? |
| A. | 0.15 kg |
| B. | 0.2 kg |
| C. | 0.25 kg |
| D. | 0.3 kg |
| Answer» D. 0.3 kg | |
| 302. |
*/*_Number of working strokes per min. for a two stroke cycle engine is _________ the speed of the engine in r.p.m.? |
| A. | Equal to |
| B. | One-half |
| C. | Twice |
| D. | Four-times |
| Answer» B. One-half | |
| 303. |
*/*_A spark plug gap is kept from? |
| A. | 0.3 to 0.7 mm |
| B. | 0.2 to 0.8 mm |
| C. | 0.4 to 0.9 mm |
| D. | 0.6 to 1.0 mm |
| Answer» B. 0.2 to 0.8 mm | |
| 304. |
*/*_The turbine of the turboprop engine is __________ that of the turbojet engine.? |
| A. | Same as |
| B. | Smaller than |
| C. | Bigger than |
| D. | None of these |
| Answer» D. None of these | |
| 305. |
*/*_In a four stroke cycle petrol engine, the compression? |
| A. | Starts at 40° after bottom dead centre and ends at 30° before top dead centre |
| B. | Starts at 40° before bottom dead centre and ends at 30° after bottom dead centre |
| C. | Starts at bottom dead centre and ends at top dead centre |
| D. | May start and end anywhere |
| Answer» B. Starts at 40¬¨‚àû before bottom dead centre and ends at 30¬¨‚àû after bottom dead centre | |
| 306. |
*/*_The air-fuel ratio in petrol engines is controlled by? |
| A. | Controlling valve opening/closing |
| B. | Governing |
| C. | Injection |
| D. | Carburetion |
| Answer» E. | |
| 307. |
*/*_In loop scavenging, the top of the piston is? |
| A. | Flat |
| B. | Contoured |
| C. | Slanted |
| D. | Depressed |
| Answer» C. Slanted | |
| 308. |
*/*_Antiknock for compression ignition engines is? |
| A. | Napthene |
| B. | Tetra ethyl lead |
| C. | Amyl nitrate |
| D. | Hexadecane |
| Answer» D. Hexadecane | |
| 309. |
*/*_The increase of cooling water temperature in petrol engine will _________ the knocking tendency.? |
| A. | Not effect |
| B. | Decrease |
| C. | Increase |
| D. | None of these |
| Answer» D. None of these | |
| 310. |
*/*_The reference fuels for knock rating of spark ignition engines would include? |
| A. | Iso-octane and alpha-methyl naphthalene |
| B. | Normal octane and aniline |
| C. | Iso-octane and normal hexane |
| D. | Normal heptane and iso-octane |
| Answer» E. | |
| 311. |
*/*_The power actually developed by the engine cylinder of an I.C. engine is known as? |
| A. | Theoretical power |
| B. | Actual power |
| C. | Indicated power |
| D. | None of these |
| Answer» D. None of these | |
| 312. |
*/*_Which of the following statements is correct?? |
| A. | All the irreversible engines have same efficiency |
| B. | All the reversible engines have same efficiency |
| C. | Both Rankine and Carnot cycles have same efficiency between same temperature limits |
| D. | All reversible engines working between same temperature limits have same efficiency |
| Answer» E. | |
| 313. |
*/*_Supercharging is the process of supplying the intake air to the engine cylinder at a density _________ the density of the surrounding atmosphere.? |
| A. | Equal to |
| B. | Less than |
| C. | Greater than |
| D. | None of these |
| Answer» D. None of these | |
| 314. |
*/*_The compression ignition engines are governed by? |
| A. | Hit and miss governing |
| B. | Qualitative governing |
| C. | Quantitative governing |
| D. | Combination of (B) and (C) |
| Answer» C. Quantitative governing | |
| 315. |
*/*_The pressure at the end of compression in the case of diesel engine is of the order of? |
| A. | 6 kg/cm |
| B. | 12 kg/cm |
| C. | 20 kg/cm |
| D. | 35 kg/cm |
| Answer» E. | |
| 316. |
*/*_The voltage required to produce a spark across the gap, between the sparking points is? |
| A. | 2000 to 4000 volts |
| B. | 4000 to 6000 volts |
| C. | 6000 to 10,000 volts |
| D. | 10,000 to 12,000 volts |
| Answer» D. 10,000 to 12,000 volts | |
| 317. |
*/*_The correct mixture strength (by weight) for petrol is about? |
| A. | 14.6 : 1 |
| B. | 18.5 : 1 |
| C. | 20.4 : 1 |
| D. | 22.6 : 1 |
| Answer» B. 18.5 : 1 | |
| 318. |
*/*_Theoretically, a four stroke cycle engine should develop _________ power as that of a two stroke cycle engine.? |
| A. | Half |
| B. | Same |
| C. | Double |
| D. | Four times |
| Answer» B. Same | |
| 319. |
*/*_In a cycle, the spark lasts roughly for? |
| A. | 1 sec |
| B. | 0.1 sec |
| C. | 0.01 sec |
| D. | 0.001 sec |
| Answer» E. | |
| 320. |
*/*_The ratio of the brake power to the indicated power is called? |
| A. | Mechanical efficiency |
| B. | Overall efficiency |
| C. | Indicated thermal efficiency |
| D. | Volumetric efficiency |
| Answer» B. Overall efficiency | |
| 321. |
*/*_In an internal combustion engine, the process of removing the burnt gases from the combustion chamber of the engine cylinder is known as? |
| A. | Scavenging |
| B. | Detonation |
| C. | Supercharging |
| D. | Polymerisation |
| Answer» B. Detonation | |
| 322. |
*/*_The ratio of indicated thermal efficiency to the corresponding air standard cycle efficiency is called? |
| A. | Net efficiency |
| B. | Efficiency ratio |
| C. | Relative efficiency |
| D. | Overall efficiency |
| Answer» D. Overall efficiency | |
| 323. |
*/*_Solid fuel fabricated into various small shapes, which are assembled to form fuel elements, is in the form of? |
| A. | Plates |
| B. | Pallets |
| C. | Pins |
| D. | All of these |
| Answer» E. | |
| 324. |
*/*_A diesel engine, during suction stroke, draws? |
| A. | Air only |
| B. | Diesel only |
| C. | A mixture of diesel and air |
| D. | None of these |
| Answer» B. Diesel only | |
| 325. |
*/*_The delay period in compression ignition engines depends upon? |
| A. | Temperature and pressure in the cylinder at the time of injection |
| B. | Nature of the fuel mixture strength |
| C. | Relative velocity between the fuel injection and air turbulence pressure of residual gases |
| D. | All of the above |
| Answer» E. | |
| 326. |
*/*_The specific fuel consumption of a petrol engine compared to diesel engine of same H.P. is? |
| A. | Same |
| B. | More |
| C. | Less |
| D. | Less or more depending on operating conditions |
| Answer» C. Less | |
| 327. |
*/*_Pick up the wrong statement? |
| A. | 2-stroke engine can run in any direction |
| B. | In 4-stroke engine, a power stroke is obtained in 4-strokes |
| C. | Thermal efficiency of 4-stroke engine is more due to positive scavenging |
| D. | Petrol engines occupy more space than diesel engines for same power output |
| Answer» E. | |
| 328. |
*/*_The air standard efficiency of an I.C. engine depends on? |
| A. | Fuel used |
| B. | Speed of engine |
| C. | Compression ratio |
| D. | None of these |
| Answer» D. None of these | |
| 329. |
*/*_A petrol engine has compression ratio from? |
| A. | 6 to 10 |
| B. | 10 to 15 |
| C. | 15 to 25 |
| D. | 25 to 40 |
| Answer» B. 10 to 15 | |
| 330. |
*/*_Compression ratio of I.C. Engines is? |
| A. | The ratio of volumes of air in cylinder before compression stroke and after compression stroke |
| B. | Volume displaced by piston per stroke and clearance volume in cylinder |
| C. | Ratio of pressure after compression and before compression |
| D. | Swept volume/cylinder volume |
| Answer» B. Volume displaced by piston per stroke and clearance volume in cylinder | |
| 331. |
*/*_The frictional power (F.P.) is given by? |
| A. | F.P. = B.P. - I.P. |
| B. | F.P. = I.P. - B.P. |
| C. | F.P. = B.P./I.P. |
| D. | F.P. = I.P./B.P. |
| Answer» C. F.P. = B.P./I.P. | |
| 332. |
*/*_The colour of exhaust from diesel engine is generally? |
| A. | White |
| B. | Bluish |
| C. | Black |
| D. | Violet |
| Answer» D. Violet | |
| 333. |
*/*_Which of the following fuel has little tendency towards detonation?? |
| A. | Benzene |
| B. | Iso-octane |
| C. | Normal heptane |
| D. | Alcohol |
| Answer» C. Normal heptane | |
| 334. |
*/*_The term scavenging is generally associated with? |
| A. | 2-stroke cycle engines |
| B. | 4-stroke cycle engines |
| C. | Aeroplane engines |
| D. | High efficiency engines |
| Answer» E. | |
| 335. |
*/*_All heat engines utilize? |
| A. | Low heat value of oil |
| B. | High heat value of oil |
| C. | Net calorific value of oil |
| D. | Calorific value of fuel |
| Answer» B. High heat value of oil | |
| 336. |
*/*_If one cylinder of a diesel engine receives more fuel than the others, then for that cylinder the? |
| A. | Exhaust will be smoky |
| B. | Piston rings would stick into piston grooves |
| C. | Engine starts overheating |
| D. | Scavenging occurs |
| Answer» E. | |
| 337. |
*/*_The thermal efficiency of a petrol engine is _________ as compared to diesel engine.? |
| A. | Same |
| B. | Less |
| C. | More |
| D. | None of these |
| Answer» C. More | |
| 338. |
*/*_The basic requirement of a good combustion chamber is? |
| A. | Minimum turbulence |
| B. | Low compression ratio |
| C. | High thermal efficiency and power output |
| D. | Low volumetric efficiency |
| Answer» D. Low volumetric efficiency | |
| 339. |
*/*_Air fuel ratio for idling speed of a petrol engine is approximately? |
| A. | 1 : 1 |
| B. | 5 : 1 |
| C. | 10 : 1 |
| D. | 15 : 1 |
| Answer» D. 15 : 1 | |
| 340. |
*/*_Which of the following does not relate to a spark ignition engine?? |
| A. | Ignition coil |
| B. | Spark plug |
| C. | Carburettor |
| D. | Fuel injector |
| Answer» E. | |
| 341. |
*/*_The size of inlet valve of an engine in comparison to exhaust valve is? |
| A. | More |
| B. | Less |
| C. | Same |
| D. | More/less depending on capacity of engine |
| Answer» C. Same | |
| 342. |
*/*_The normal heptane (C‚ÇáH‚ÇÅ‚ÇÜ) is given a rating of ________ octane number.? |
| A. | 0 |
| B. | 50 |
| C. | 100 |
| D. | 120 |
| Answer» B. 50 | |
| 343. |
*/*_Polymerization is a chemical process in which molecules of a compound become? |
| A. | Larger |
| B. | Slowed down |
| C. | Smaller |
| D. | Liquid |
| Answer» B. Slowed down | |
| 344. |
*/*_A two stroke cycle engine gives ________ the number of power strokes as compared to the four stroke cycle engine, at the same engine speed.? |
| A. | Half |
| B. | Same |
| C. | Double |
| D. | Four times |
| Answer» D. Four times | |
| 345. |
*/*_Diesel as compared to petrol is? |
| A. | Highly ignitable |
| B. | More difficult to ignite |
| C. | Less difficult to ignite |
| D. | None of these |
| Answer» C. Less difficult to ignite | |
| 346. |
*/*_The purpose of testing an internal combustion engine is? |
| A. | To determine the information, which cannot be obtained by calculations |
| B. | To conform the data used in design, the validity of which may be doubtful |
| C. | To satisfy the customer regarding the performance of the engine |
| D. | All of the above |
| Answer» E. | |
| 347. |
*/*_Number of working strokes per min. for a four stroke cycle engine are _________ the speed of the engine in r.p.m.? |
| A. | Equal to |
| B. | One-half |
| C. | Twice |
| D. | Four-times |
| Answer» C. Twice | |
| 348. |
*/*_In a four stroke cycle diesel engine, the compression? |
| A. | Starts at 40° after bottom dead center and ends at 10° before top dead center |
| B. | Starts at 40° before top dead center and ends at 40° after top dead center |
| C. | Starts at top dead center and ends at 40° before bottom dead center |
| D. | May start and end anywhere |
| Answer» B. Starts at 40¬¨‚àû before top dead center and ends at 40¬¨‚àû after top dead center | |
| 349. |
*/*_The inlet valve of a four stroke cycle internal combustion engine remains open for? |
| A. | 130° |
| B. | 180° |
| C. | 230° |
| D. | 270° |
| Answer» D. 270¬¨‚àû | |
| 350. |
*/*_In a four stroke cycle engine, the sequence of operations is? |
| A. | Suction, compression, expansion and exhaust |
| B. | Suction, expansion, compression and exhaust |
| C. | Expansion, compression, suction and exhaust |
| D. | Compression, expansion, suction and exhaust |
| Answer» B. Suction, expansion, compression and exhaust | |