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.
| 1. |
Aim of engine testing is |
| A. | to get specified information |
| B. | to justify rating of engine |
| C. | to validate design data |
| D. | all the above |
| Answer» E. | |
| 2. |
Indicator diagram is used to measure |
| A. | imep |
| B. | speed |
| C. | temperature |
| D. | f.p. |
| Answer» B. speed | |
| 3. |
Heat losses in an engine are indicative of |
| A. | thermal efficiency of engine |
| B. | indicated power |
| C. | brake power |
| D. | none of the above |
| Answer» B. indicated power | |
| 4. |
Power developed within the cylinder is called |
| A. | i.p. |
| B. | b.p. |
| C. | f.p. |
| D. | unavailable power |
| Answer» B. b.p. | |
| 5. |
Power available at output shaft is called |
| A. | i.p. |
| B. | b.p. |
| C. | f.p. |
| D. | unavailable power |
| Answer» C. f.p. | |
| 6. |
Best method to measure indicated mean effective pr (imep) is by |
| A. | mechanical indicator |
| B. | electronic indicator |
| C. | electrical indicator |
| D. | all are equal efficient |
| Answer» C. electrical indicator | |
| 7. |
Mechanical losses in engine equal to |
| A. | b.p/i.p |
| B. | i.p./b.p |
| C. | i.p./b.p. |
| D. | b.p./i.p |
| Answer» D. b.p./i.p | |
| 8. |
Mechanical indicators are suitable to measure imp in case of |
| A. | low speed engine up to 1500 rpm |
| B. | medium speed engines (1500-3000) |
| C. | high speed engines more than 3000 rpm |
| D. | none of the above |
| Answer» B. medium speed engines (1500-3000) | |
| 9. |
If a= net area of diagram in mm , l= length of indicator diagram in cm & k= spring constant in N/m /m the imp in bar equals |
| A. | (a/l)xk |
| B. | (a/l) x k x 10 |
| C. | (a/l) x k x 10 |
| D. | (a/l) x k x 10 |
| Answer» C. (a/l) x k x 10 | |
| 10. |
Indicator diagram is the plot of_____on cartesian co-ordinates. |
| A. | p-v |
| B. | p-t |
| C. | t-v |
| D. | t-p |
| Answer» B. p-t | |
| 11. |
Engine indicator is used to measure |
| A. | bmep |
| B. | imep |
| C. | b.p |
| D. | i.p |
| Answer» C. b.p | |
| 12. |
If work developed by the engine per cycle is W, then the indicated mean effective pr equals to |
| A. | w |
| B. | w / stroke volume |
| C. | w / length of stroke |
| D. | w x stroke volume |
| Answer» C. w / length of stroke | |
| 13. |
Best method to measurement of B.P. is |
| A. | rope brake dynamometer |
| B. | prony brake dynamometer |
| C. | hydraulic dynamometer |
| D. | all are equal |
| Answer» D. all are equal | |
| 14. |
Which of the dynamometer cannot be used for measurement of B.P. at high speeds |
| A. | prony brake |
| B. | hydraulic |
| C. | swing field |
| D. | none of the above |
| Answer» B. hydraulic | |
| 15. |
Which of the following dynamometer is suitable to measure B.P. of an aircraft |
| A. | prony brake |
| B. | hydraulic |
| C. | swinging field |
| D. | eddy current |
| Answer» E. | |
| 16. |
Modern SI engine use F head combustion chamber because of |
| A. | provides high turbulence |
| B. | provides shorter flame travel |
| C. | low surface to volume ratio |
| D. | all of the above |
| Answer» E. | |
| 17. |
actual number of stroke per min will be equll to |
| A. | theroricl stroke per min + missed stroke per min |
| B. | theroricl stroke per min x missed stroke per min |
| C. | theroricl stroke per min - missed stroke per min |
| D. | none of the above |
| Answer» D. none of the above | |
| 18. |
If n heptane in a mixture of iso octane and n-heptane by volume is 30%.Its octane rating is |
| A. | 30 |
| B. | 70 |
| C. | 50 |
| D. | none of the above |
| Answer» C. 50 | |
| 19. |
Iso octane in a fuel for petrol engine |
| A. | reduces auto-ignition |
| B. | promotes auto-ignition |
| C. | has no effect on autoignition |
| D. | none of the above |
| Answer» B. promotes auto-ignition | |
| 20. |
If a fuel for SI engine has high octane rating it shows that fuel has |
| A. | high volatility of fuel |
| B. | high calorific value |
| C. | lower ignition delay |
| D. | higher ignition delay |
| Answer» E. | |
| 21. |
To assign knock rating of fuels for SI engines the fuels are considered as |
| A. | alpha methyl napthelene and iso-octane |
| B. | 2,2,4 trimethyl pentane and n-heptane |
| C. | alpha- methyl napthelene and n-heptane |
| D. | none of the above |
| Answer» C. alpha- methyl napthelene and n-heptane | |
| 22. |
MON means ___ |
| A. | metal oxygen number |
| B. | motor oxygen number |
| C. | metal octane number |
| D. | motor octane number |
| Answer» E. | |
| 23. |
Highest usefuel compression ratio relates to |
| A. | maximum power |
| B. | maximum efficiency |
| C. | the engine can be run without detonation |
| D. | none of the above |
| Answer» D. none of the above | |
| 24. |
Petrol available in the market has octane rating as |
| A. | 40 to 50 |
| B. | 51 to 75 |
| C. | 70 to 80 |
| D. | 86 to 100 |
| Answer» D. 86 to 100 | |
| 25. |
Ignition quality of SI engine fuels is expressed as |
| A. | octane rating |
| B. | volatility rating |
| C. | api gravity rating |
| D. | none of the above |
| Answer» B. volatility rating | |
| 26. |
Performance number gives rating of fuel with |
| A. | octane number less than 1 |
| B. | octane number more than 1 |
| C. | octane number less than 100 |
| D. | octane number more than 100 |
| Answer» E. | |
| 27. |
Toluene and heptane are reference fuels used in |
| A. | octane rating |
| B. | heptane rating |
| C. | toluene rating |
| D. | d.n.rating |
| Answer» D. d.n.rating | |
| 28. |
Performance number= |
| A. | knock limited imep of test fuel - knock limited imep of iso octane |
| B. | knock limited imep of test fuel + knock limited imep of iso octane |
| C. | knock limited imep of test fuel x knock limited imep of iso octane |
| D. | knock limited imep of test fuel /knock limited imep of iso octane |
| Answer» E. | |
| 29. |
HUCR represents the compression ratio at which |
| A. | power output |
| B. | fuel comsumption is minimum |
| C. | engine can run without detonation |
| D. | none of the above |
| Answer» D. none of the above | |
| 30. |
In SI enginesmaximum amount of fuel is burnt during the stage____ |
| A. | pre-burning |
| B. | ignition lag |
| C. | flame propagation |
| D. | after burning |
| Answer» D. after burning | |
| 31. |
Compensating devices are provided in carburetor |
| A. | to vary quantity of mixture according to the load on the engine |
| B. | to supply af ratio always as needed by economy running |
| C. | to vary af ratio according to various operating conditions |
| D. | to supply rich mixtures during acceleration only |
| Answer» C. to vary af ratio according to various operating conditions | |
| 32. |
Combustion is defined as |
| A. | rapid oxidation to liberate energy in the form of heat |
| B. | its a chemical reaction of contents of fuel and oxygen in the air to produce energy in the form of heat. |
| C. | both a and b |
| D. | only a |
| Answer» D. only a | |
| 33. |
Sensitivity shows |
| A. | change in eprformance of fuel under test condition and practical condition |
| B. | change in octane number |
| C. | ratio of octane number of ideal fuel and actual fuel |
| D. | ratio of octane number of actual fuel to ideal fuel. |
| Answer» B. change in octane number | |
| 34. |
thermal efficiency varries |
| A. | inversely as specific fuel consumption |
| B. | directly as specific fuel consumption |
| C. | as square as specific fuel consumption |
| D. | as root as specific fuel consumption |
| Answer» B. directly as specific fuel consumption | |
| 35. |
In T-head combution chamber, spark plug is located |
| A. | near intake valve |
| B. | centrally |
| C. | near exhaust valve |
| D. | near injector |
| Answer» D. near injector | |
| 36. |
Performance number of iso-octane is |
| A. | 1 |
| B. | 100 |
| C. | zero |
| D. | 50 |
| Answer» C. zero | |
| 37. |
Higher sensitivity of fuel shows___ |
| A. | better performance under serve conditions. |
| B. | poor oerformance under serve conditions |
| C. | better emissions under serve conditions |
| D. | less emissions under serve conditions |
| Answer» C. better emissions under serve conditions | |
| 38. |
Ideal fuel for SI engine should have |
| A. | low sit |
| B. | high sit |
| C. | low cv |
| D. | less volatility |
| Answer» C. low cv | |
| 39. |
Which is not true about L-head combution chamber? |
| A. | high rate of combustion |
| B. | more tendency to detonate |
| C. | permits low compression ratio |
| D. | requires less maintenance |
| Answer» B. more tendency to detonate | |
| 40. |
The maximum compression ratio which can be used without knocking is |
| A. | hcr |
| B. | hucr |
| C. | pn |
| D. | on |
| Answer» C. pn | |
| 41. |
Main drawback of T-head combution chamber is |
| A. | more maintenance |
| B. | permits more compression ratio |
| C. | more flame travel |
| D. | permits less compression ratio |
| Answer» E. | |
| 42. |
Which is not true about I-head combution chamber? |
| A. | higher volumetric efficiency |
| B. | non-uniform pressure rise |
| C. | permits higher compression ratio |
| D. | less flame travel |
| Answer» C. permits higher compression ratio | |
| 43. |
Main drawback of F-Head combution chamber is |
| A. | improper positioning of spark plug |
| B. | more knocking tendency |
| C. | less efficiency |
| D. | difficult manufacturing |
| Answer» E. | |
| 44. |
For petrol engine the method of governing is |
| A. | hit and miss governing |
| B. | quality governing |
| C. | quantity governing |
| D. | none of the above |
| Answer» D. none of the above | |
| 45. |
The drawbacks of carburetor includes |
| A. | non uniform distribution in multi cylinder engines |
| B. | less breathing capacity |
| C. | slow response to change in operating conditions |
| D. | all of the above |
| Answer» E. | |
| 46. |
The choke in automobile carburettor system is meant for supplying |
| A. | lean mixture |
| B. | rich mixture |
| C. | stoichiometric mixture |
| D. | weak mixture |
| Answer» C. stoichiometric mixture | |
| 47. |
For maximum thermal efficiency aim is to |
| A. | use all the oxygen present in combustion chamber |
| B. | use all the fuel present in combustion chamber |
| C. | to get maximum pressure in the cylinder |
| D. | to get maximum temperature in the cylinder |
| Answer» C. to get maximum pressure in the cylinder | |
| 48. |
During sudden acceleration, engine requires |
| A. | rich mixture |
| B. | chemically correct mixture |
| C. | lean mixture |
| D. | may be lean or rich mixture |
| Answer» B. chemically correct mixture | |
| 49. |
The main jet of the main metering system is situated |
| A. | above the level of the petrol in float chamber |
| B. | below the level of the petrol in float chamber |
| C. | at the same level |
| D. | any arrangement can be possible |
| Answer» B. below the level of the petrol in float chamber | |
| 50. |
To get maximum power aim is |
| A. | to use all fuel in combustion chamber |
| B. | to utilize all oxygen in combustion chamber |
| C. | to get more economy |
| D. | to get less fuel consumption |
| Answer» C. to get more economy | |