Which is correct statement about reaction time for autoignition 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 mini-mum reaction time
(D) all of the above
(D) non of the above
Ignition lag is__________________?
(A) the time taken by fuel after injection (before top dead center) to reach upto auto-ignition temperature
(B) time before actual fuel injection and the pump plunger starts to pump fuel
(C) time corresponding to actual injection and top dead center
(D) time corresopnding to actual ingition and top dead center
(D) none of the above
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
(D) preignition
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
(D) mixture of cetane with tetra-ethyl lead
The self-ignition temperature of diesel oil compared to petrol is_________________?
(A) higher
(B) lower
(C) same
(D) depends on quality of fuel
(D) unpredictable
Cetane___________________?
(A) has zero cetane number
(B) has 100 cetane number
(C) helps detonation
(D) is a straight chain paraffin
(D) determines the efficiency of an I.
Iso-oct ,ne________________?
(A) has octane number of 0
(B) has octane number of 50
(C) has octane number of 100
(D) is an index of detonation quality
(D) is an index of knocking quality
Kerosene is distilled at________________?
(A) 30 – 65°C
(B) 65 – 220°C
(C) 220 – 350°C
(D) 350 – 450°C
(D) 450-550°C
Which is false statement about advantages of V-type engine_________________?
(A) compact design requiring lesser space
(B) improved distribution of air to cylinder
(C) casting less liable to distortion
(D) reduced torsional vibration because of shorter crankshaft
(D) less overhead clearance
Detonation is caused by the following unstable compounds______________________?
(A) peroxides, aldehydes and ketones
(B) peroxides, aldehydes, oxides and sul-phides
(C) aldehydes, oxides and ketones
(D) ketones and sulphur compounds
(D) none of the above