Diesel engine can work on very lean air fuel ratio of the order of 30: 1. A petrol engine can also work on such a lean ratio provided
It is properly designed
Best quality fuel is used
Cannot work as it is impossible
Flywheel size is proper
Correct Answer :
C. Cannot work as it is impossible
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Arrangement of the cylinders
Design of crankshaft
Number of cylinders
All of these
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White
Bluish
Black
Violet
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0.25 kg
0.3 kg
0.35 kg
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Net calorific value of oil
Calorific value of fuel
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Just about the same difficult to ignite
More difficult to ignite
Highly ignitable
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Heterogeneous
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20 bar
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1 : 1
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Increase
Reduce
Not effect
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Opens at top dead center and closes at bottom dead center
Opens at 10° after top dead center and closes 20° before the bottom dead center
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Equal to
Less than
Greater than
None of these
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The petrol engines are costly than diesel engines
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kcal
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Tetra ethyl lead
Amyl nitrate
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Starts at 40° before bottom dead centre and ends at 30° after bottom dead centre
Starts at bottom dead centre and ends at top dead centre
May start and end anywhere
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Normal octane and aniline
Isooctane and normal hexane
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Starts at top dead centre and ends at bottom dead centre
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Net calorific value
Calorific value
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75% normal heptane and 25% iso-octane
75% petrol and 25% diesel
75% diesel and 25% petrol
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Spark ignition
Compression ignition
Both (A) and (B)
None of these
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Less
Same
More/less depending on capacity of engine
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Diesel cycle
Dual combustion cycle
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Diesel engine can work on very lean air fuel ratio of the order of 30: 1. A petrol engine can also work on such a lean ratio provided
It is properly designed
Best quality fuel is used
Cannot work as it is impossible
Flywheel size is proper
The air standard efficiency of an Otto cycle compared to diesel cycle for the given compression ratio is
Same
Less
More
More or less depending on power rating