211. During idling stage, gasoline does not flow through the carburetor tube because of
A.Pressure drop
B.High pressure
C.Venturi vacuum
D.It is not desired to be passed through main tube

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212. Thermal efficiency of I.C. engine on weak mixture is
A.Higher
B.Lower
C.Unaffected
D.Higher/lower depending on engine rating

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213. In petrol engine the actual pressure developed compared to the predicted maximum pressure is
A.90%
B.70%
C.50%
D.25%

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214. Octane number of petrol normally used in petrol engines is of the order of
A.20-30
B.40-60
C.60-70
D.80-90

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215. A fuel of octane rating 85 matches the anti knock qualities of a mixture consisting of 85% and 15% respectively of
A.Iso-octane and normal heptane
B.Normal heptane and iso-octane
C.Petrol and diesel
D.Benzene and methyl alcohol

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216. Octane number of petrol available from Indian refineries of the order of
A.50
B.72
C.13
D.94

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217. Octane number of iso-octane is about
A.0
B.100
C.80
D.90

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