106. Ethyl fluid is used
A.To increase the octane rating of the fuel
B.To increase the cetane rating of the fuel
C.As a defrosting agent
D.As a superior type of fluid compared to others
107. The self-ignition temperature of diesel oil compared to petrol is
A.Higher
B.Lower
C.Same
D.Depends on quality of fuel
108. Normal heptane
A.Accelerates auto-ignition
B.Helps to resist auto-ignition
C.Does not affect auto-ignition has no relation with auto-ignition
D.Retards auto-ignition
109. Cetane number is determined by comparing the performance of diesel oil with the following hydrocarbons
A.Cetane
B.Mixture of cetane and alphamethyl napthalene
C.Ethylene dibromide
D.Mixture of aldehydes and ketones
110. Which is correct statement about reaction time for auto-ignition of fuel and the fuel air ratio
A.Lean mixture has high reaction time
B.Rich mixture has high reaction time
C.Chemically correct mixture has minimum reaction time
D.All of the above
111. Violent sound pulsations within the cylinder of an I.C. engine are caused due to
A.Heavy turbulence
B.Improved scavenging
C.Heavy supercharging
D.Detonation
112. Auto-ignition temperature is
A.Minimum temperature to which oil is heated in order to give off inflammable vapors in sufficient quantity to ignite momentarily when brought in contact with a flame
B.Temperature at which it solidifies or congeals
C.That at which it catches fire without external aid
D.Indicated by 90% distillation temperature, i.e., when 90% of sample oil has distilled off
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