Questions and Answers Section 7

Questions and Answers

Question :

61.If the air-fuel mixture in a spark ignition engine is too rich, then airfuel ratio is about

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10:1

Note:-The correct mixture is the mixture which can combust completely, cleanly, and with a minimum of detonation at the given engine speed and cylinder temperature. A lean mixture has too little fuel in the mix for proper combustion, a rich mixture has too much fuel in the mix for proper combustion.

Question :

62.If the air-fuel mixture ignites before the spark takes place at spark plug, the condition is called

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pre-ignition

Note:-the premature combustion of the fuel–air mixture in an internal combustion engine.

Question :

63.The advantage of a tubeless tyre over tube type tyre is 

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slow air leakage

better fuel efficiency

less chances of running flat

all of these

Question :

64.The gear shift lever requires two separate motions to shift gears, and the first movement

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selects the synchronizer 

Question :

65.The Diesel engines as compared to petrol engines require 

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bigger flywheel

Question :

66.In a forced feed lubrication system, the device used to guard against excessive oil pressure, is known as

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relief valve

Question :

67.When the vehicle is at rest, the clutch is in 

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engaged position

Question :

68.Which of the following oil is more viscous ?

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SAE 80

Note:-SAE stands for Society of Automobile Engineers and they standardise a lot of components that are used to build an automobile. 

Question :

69.Odometer is an instrument used for measurement of

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distance




Question :

70.In Diesel engines, the duration between the time of injection and the time of ignition is called

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delay period.