The specific fuel consumption per BH hour for a petrol engine is approximately
0.15 kg
0.2 kg
0.25 kg
0.3 kg
Correct Answer :
C. 0.25 kg
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Energy of neutrons
Properties of the reflector
All of these
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Less
Same
More/less depending on capacity of engine
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Leaking piston rings
Use of thick head gasket
Clogged air inlet slots
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Very low
High
Very high
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2-stroke petrol engine
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Diesel engine
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125°
235°
200°
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Paraffin, napthene, aromatic
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Aeroplane engines
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Same
Lower
Higher
None of these
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In compression ignition engines, detonation occurs near the beginning of combustion.
Since the fuel, in compression ignition engines, is injected at the end of compression stroke, therefore, there will be no pre-ignition.
To eliminate knock in compression ignition engines, we want to achieve auto-ignition not early and desire a long delay period.
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Is lighter
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1 - rγ - 1
1 + rγ - 1
1 - (1/rγ - 1)
None of these
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4 %
8 %
14 %
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Chemically correct mixture
About 35% of rich mixture
About 10% of rich mixture
A fuel of an octane number rating of 75 matches in knocking intensity as a mixture of
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75% petrol and 25% diesel
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Chemically correct air-fuel ratio by volume
Actual air-fuel ratio for maximum efficiency
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1000-1500°C
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180°
230°
270°
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Same
Double
Four times
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Design of crankshaft
Number of cylinders
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12 : 1
15 : 1