MCQOPTIONS
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MCQOPTIONS
This section includes 471 Mcqs, each offering curated multiple-choice questions to sharpen your Uncategorized topics knowledge and support exam preparation. Choose a topic below to get started.
| 301. |
Petrol is mixture of hydrocarbons having |
| A. | same boiling points |
| B. | different boiling points |
| C. | more boiling points |
| D. | none of the above |
| Answer» C. more boiling points | |
| 302. |
During maximum power requirement rich mixture provided also has advantage of |
| A. | decreasing temperature of exhaust manifold which is overheated at high load |
| B. | reducing flame temperature and the cylinder temperature |
| C. | avoids detonation because of prevention of overheating of exhaust valve |
| D. | all of the above |
| Answer» E. | |
| 303. |
A carburetor which is installed above intake manifold and flow ofmixture is assited by gravity is called |
| A. | up draught carburetor |
| B. | down draught carburetor |
| C. | side draught carburetor |
| D. | none of the above |
| Answer» C. side draught carburetor | |
| 304. |
An emulsion tube or air bleed method is used in modern carburetor |
| A. | to maintain air fuel ratio at all speeds |
| B. | to increase af ratio with decrease in load |
| C. | to decrease af ratio with increase in speed |
| D. | none of the above |
| Answer» B. to increase af ratio with decrease in load | |
| 305. |
Nozzle lip is |
| A. | level difference between level of fuel in throttle valve and level of fuel in float chamber |
| B. | it is tip of main jet |
| C. | it is pressure difference |
| D. | level difference between level of tip of main jet and level of fuel in float chamber |
| Answer» E. | |
| 306. |
Continuous port fuel injection refers to injection of fuel |
| A. | near the inlet port |
| B. | near the inlet manifold |
| C. | directly into the cylinder |
| D. | none of the above |
| Answer» B. near the inlet manifold | |
| 307. |
The nozzle lip is the level difference between |
| A. | venturi and level of petrol in float chamber |
| B. | venturi and throttle valve |
| C. | throttle valve and choke valve |
| D. | none of the above |
| Answer» B. venturi and throttle valve | |
| 308. |
what would be the mass flow rate of the gasoline in kg/s, the engine sonsumes 8lit/hr of gasoline, taking density of gasoline is 800 kg/cubic meter |
| A. | 0.00125 |
| B. | 0.00178 |
| C. | 0.2345 |
| D. | 0.0123 |
| Answer» C. 0.2345 | |
| 309. |
In MPFI injection system |
| A. | each cyclider has separate fuel injector |
| B. | injectors are mounted on the inlet ports |
| C. | fuel from fuel tank is pumped under pressure |
| D. | all of the above |
| Answer» E. | |
| 310. |
With increasing Air-Fuel ratio in S I engine Maximum power |
| A. | increases in the leaner region of the mixture |
| B. | decreases in the richer region of the mixture |
| C. | first increases up to a point at which maximum power is obtained and then it is decreases on the leaner side of the mixture |
| D. | all of the above |
| Answer» D. all of the above | |
| 311. |
Fuel economy from the engine can be expected |
| A. | when engine is running at normal speed |
| B. | when engine is running at very very low speed |
| C. | when engine is running at high speed |
| D. | when engine is running at very very high speed |
| Answer» B. when engine is running at very very low speed | |
| 312. |
2,2,4 trimethyl pentane has octane number equal to |
| A. | 1 |
| B. | 0 |
| C. | 100 |
| D. | 120 |
| Answer» D. 120 | |
| 313. |
Requirements of carburetor are |
| A. | to meter the liquid in such a quantity that air-fuel ratio is changed according to steady and transient working conditions of an engine |
| B. | to prepare homogeneous air-fuel mixture |
| C. | to provide rich mixture during idling and acceleration |
| D. | all of the above |
| Answer» E. | |
| 314. |
In a SI engine for maximum power, relative fuel-air ratio is |
| A. | 1.5 |
| B. | 1.2 |
| C. | 0.8 |
| D. | 0.6 |
| Answer» C. 0.8 | |
| 315. |
Petrol fuel which is more volatile are called |
| A. | heavy ends |
| B. | more ends |
| C. | light ends |
| D. | bulky ends |
| Answer» D. bulky ends | |
| 316. |
Which is not an advantage of MPFI system? |
| A. | uniform air fuel ratio to each cylinder |
| B. | ease of cold starting |
| C. | low sfc |
| D. | elaborate arrangement of components |
| Answer» E. | |
| 317. |
Which of the following is not the requirement of the carburetor |
| A. | prepare af ratio as required during starting, idling, maximum power and acceleration |
| B. | prepare non homogeneous mixture |
| C. | energy is supplied to change fuel from liquid to vapour form |
| D. | supply rich mixture during acceleration |
| Answer» C. energy is supplied to change fuel from liquid to vapour form | |
| 318. |
To reduce knocking, the fuel in SI engine should have ____ self ignition temperature |
| A. | low |
| B. | high |
| C. | any |
| D. | automatic |
| Answer» B. high | |
| 319. |
n-heptane has octane number equal to |
| A. | 0 |
| B. | 1 |
| C. | 100 |
| D. | 120 |
| Answer» B. 1 | |
| 320. |
Which air fuel ratio gives maximum power for SI engine |
| A. | 1970-01-01 15:01:00 |
| B. | 1970-01-01 18:01:00 |
| C. | 1970-01-01 08:01:00 |
| D. | 1970-01-01 12:01:00 |
| Answer» E. | |
| 321. |
For SI engine for maximum power, relative fuel air ratio should be |
| A. | 0.6 |
| B. | 0.8 |
| C. | 1 |
| D. | 1.2 |
| Answer» E. | |
| 322. |
The use of vent on a float chamber ensures |
| A. | filling of petrol if level of petrol goes down |
| B. | leak off connection for overflow case |
| C. | maintaining atmospheric pressure in float chamber |
| D. | none of the above |
| Answer» D. none of the above | |
| 323. |
For octane rating a standard reference fuel consists of |
| A. | iso-octane only |
| B. | n-heptane only |
| C. | combination of 2,2,4 trimethyl pentane and n-heptane |
| D. | combination of iso heptane and n-octane |
| Answer» D. combination of iso heptane and n-octane | |
| 324. |
To reduce knocking in SI engines, self ignition temperature of fuel should be ____ |
| A. | high |
| B. | low |
| C. | varying |
| D. | constant |
| Answer» B. low | |
| 325. |
To prevent knocking flame propagation should be |
| A. | retareded |
| B. | accelerated |
| C. | sinusoidal |
| D. | upfront |
| Answer» B. accelerated | |
| 326. |
Knocking in SI engines will be less if |
| A. | delay period is less and flame speed is high. |
| B. | delay period is less and flame speed is less |
| C. | delay period is high and flame speed is high |
| D. | delay period is high and flame speed is less |
| Answer» D. delay period is high and flame speed is less | |
| 327. |
The carburetor depression is |
| A. | the pressure drop because of whch air is sucked inside |
| B. | the pressure drop because of which fuel is sucked |
| C. | the pressure drop because of charge is taken inside the cylinder |
| D. | all of the above |
| Answer» C. the pressure drop because of charge is taken inside the cylinder | |
| 328. |
As load increases, the knocking tendency of SI engines____ |
| A. | increases |
| B. | decreases |
| C. | cant predict |
| D. | remains same |
| Answer» B. decreases | |
| 329. |
Carburetor depression is a |
| A. | velocity difference |
| B. | temperature difference |
| C. | pressure difference |
| D. | none of the above |
| Answer» D. none of the above | |
| 330. |
The pressure difference between float chamber and throat is |
| A. | nozzle lip |
| B. | nozzle dip |
| C. | carburetor depression |
| D. | potential difference |
| Answer» D. potential difference | |
| 331. |
Which is not the advantage of gasoline injection as compared to carburetor |
| A. | exact af ratio at all loads |
| B. | same mixture strengths to all cylinders |
| C. | economy of fuel during idling and low load running |
| D. | low volumetric efficiency |
| Answer» E. | |
| 332. |
Which is not a method of fuel injection in SI engine |
| A. | directly into the cylinder before the end of compression stroke |
| B. | in to the inlet manifold during suction stroke |
| C. | near inlet port during suction stroke |
| D. | directly into the cylinder in high pressure injection system |
| Answer» B. in to the inlet manifold during suction stroke | |
| 333. |
Carburetor is designed |
| A. | to get easy combustion in engine |
| B. | to meter the liquid quantity to prepare the required air-fuel mixture which varies with load on engine |
| C. | it supporting device in piping |
| D. | it is a acting as a fuel and air mixer |
| Answer» C. it supporting device in piping | |
| 334. |
Correct sequence of combustion stages in SI engine is |
| A. | propagation of phase,ignition phase and after burning |
| B. | preparation phase,propagation of flame and after burning |
| C. | propagation of phase,preparation phase and after burning |
| D. | after burning,propagation of phase and preparation phase |
| Answer» C. propagation of phase,preparation phase and after burning | |
| 335. |
Which of the following is not the advantage of GDI |
| A. | high volumetric efficiecy |
| B. | low emissions |
| C. | ease of cold starting |
| D. | high initial cost |
| Answer» E. | |
| 336. |
Octane number 60 means, the fuel has antiknock proper equal to fuel from by |
| A. | 60% of n-octane 40% of petrol |
| B. | 60% of iso octane and 40% n-heptane |
| C. | 60% of iso octane and 40% of eptrol |
| D. | 60% of iso octane and 40% of tel |
| Answer» C. 60% of iso octane and 40% of eptrol | |
| 337. |
Fuel economy should not be expected in SI engine for which following cases |
| A. | when vehicle is climbing on hills |
| B. | when engine is pulling large quantity water from well |
| C. | both a and b |
| D. | only a |
| Answer» D. only a | |
| 338. |
Chemixally correct air fue ratio of octane is |
| A. | 13.14:1 |
| B. | 15.14:1 |
| C. | 17.14:1 |
| D. | 1.17:14 |
| Answer» C. 17.14:1 | |
| 339. |
Which of the following is not the part of fuel induction system. |
| A. | fuel filter and fuel pump |
| B. | carburettor |
| C. | throttle valve |
| D. | spark plug |
| Answer» E. | |
| 340. |
Which is correct expression? |
| A. | ron=sensitivity-mon |
| B. | sensitivity=ron/mon |
| C. | sensitivity=ron-mon |
| D. | sensitivity=mon/ron |
| Answer» D. sensitivity=mon/ron | |
| 341. |
The tip of main nozzle with reference to petrol level in float chamber is |
| A. | at the same level |
| B. | at higher level |
| C. | at lower level |
| D. | none of the above |
| Answer» C. at lower level | |
| 342. |
Stoichiometric air fuel ratio suggests |
| A. | correct quantity of fuel -air ratio which gives more economy |
| B. | correct quantity of fuel -air ratio which gives more power |
| C. | correct quantity of fuel -air ratio which gives complete combustion |
| D. | all of the above |
| Answer» D. all of the above | |
| 343. |
Knocking in SI engine occurs when___ |
| A. | flame reaches the unburnt charge before delay period is over |
| B. | flame reaches after the delay period is over |
| C. | spark is produced before charge coming in |
| D. | spark is produced several times |
| Answer» C. spark is produced before charge coming in | |
| 344. |
Air- fuel ratio must be changed with following conditions of an SI engine |
| A. | starting |
| B. | warm up |
| C. | acceleration |
| D. | all of the above |
| Answer» E. | |
| 345. |
Stoichiometric air fuel ratio of petrol is aproximately |
| A. | 1970-01-01 10:01:00 |
| B. | 1970-01-01 12:01:00 |
| C. | 1970-01-01 15:01:00 |
| D. | 1970-01-01 18:01:00 |
| Answer» D. 1970-01-01 18:01:00 | |
| 346. |
Steady operating conditions of an SI engine is |
| A. | continuous operation of engine at constant speed and for constant load on engine |
| B. | continuous operation of engine at constant speed and for changing load on engine |
| C. | continuous operation of engine at changing speed and for constant load on engine |
| D. | none of the above |
| Answer» B. continuous operation of engine at constant speed and for changing load on engine | |
| 347. |
Fuel flow area is varied in ____________ carburetor. |
| A. | solex |
| B. | zenith |
| C. | carter |
| D. | su |
| Answer» E. | |
| 348. |
Carburetor depression is pressure difference between |
| A. | pressure in float chamber and at float section in venturi |
| B. | pressure in float chamber and at throttle valve section in jet tube |
| C. | pressure in venturi section and at float section in venturi |
| D. | pressure in float chamber and at inlet section in jet tube |
| Answer» B. pressure in float chamber and at throttle valve section in jet tube | |
| 349. |
Petrol having high vapour pressures and low boiling points are called |
| A. | light ends |
| B. | heavy ends |
| C. | bulky ends |
| D. | low ends |
| Answer» B. heavy ends | |
| 350. |
Actual air fuel ratio supplied by carburetor at high altitudes compared to sea level |
| A. | lean |
| B. | rich |
| C. | same |
| D. | can t say |
| Answer» C. same | |