For same power output and same r, as compared to 2- stroke engines, four stroke SI engines have (a) Higher fuel consumption (b) Lower thermal efficiency (c) Highest exhaust temperatures (d) Higher thermal efficiency

For same power output and same r, as compared to 2- stroke engines, four stroke SI engines have (a) Higher fuel consumption (b) Lower thermal efficiency (c) Highest exhaust temperatures (d) Higher thermal efficiency
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A gas engine has a volume of 300 cc and clearance volume of 25 cc. Its volumetric efficiency is 0.8 and mech efficiency is 0.9. What is the volume of the mixture taken in per stroke? (a) 248 cc (b) 252 cc (c) 264 cc (d) 286 cc

Description : A gas engine has a volume of 300 cc and clearance volume of 25 cc. Its volumetric efficiency is 0.8 and mech efficiency is 0.9. What is the volume of the mixture taken in per stroke? (a) 248 cc (b) 252 cc (c) 264 cc (d) 286 cc

Last Answer : Ans : c

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The _____________ sensor, monitors mass or volume of air flowing into the intake manifold for adjusting the quantity of fuel. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature

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For S.I. engines fuel most preferred are a) aromatics b) paraffins c) olefins d) napthenes

Description : For S.I. engines fuel most preferred are a) aromatics b) paraffins c) olefins d) napthenes

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Which of the following statement is not correct with respect to alcohols as alternate fuel in IC engines a) anti-knock characteristics of alcohol is poor b) alcohol contains about half the heat energy of gasoline/litre c) alcohol does not vaporize as easily as gasoline d) alcohols are corrosive in nature

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The air fuel ratio in petrol engines is controlled by a. valve opening / closing b. governing c. carburetion d. scavenging

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In four stroke engine there is one power stroke in _____ of crankshaft rotation. a. 180° b. 360° c. 540° d. 720° (Ans:d)

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Velocity of flame propagation in SI engine is maximum for a fuel air mixture which is (a) 10% richer than stoichiometric (b) Equal to stoichiometric (c) More than 10% richer than stoichiometric (d) 10% leaner than stoichiometric

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An engine working on air standard Otto cycle has a cylinder diameter of 10 cm and stroke length of 15 cm. The ratio of specific heats for air is 1.4. If the clearance volume is 196.3 cc and the heat supplied per kg of air per cycle is 1800 kJ/kg, then work output per cycle per kg of air is a. 879.1 kJ/ b. 890.2 kJ c. 895.3 kJ d. 973.5 kJ

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Last Answer : ANSWER d. 973.5 kJ

Discuss the drawbacks of carbureted SI engine on the base of, Air-fuel ratio, fuel consumption, power output, emission.

Description : Discuss the drawbacks of carbureted SI engine on the base of, Air-fuel ratio, fuel consumption, power output, emission. 

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Last Answer : (D) Mercury as a pollutant can enter the blood stream & the digestive system/ lungs and is responsible for causing Minamata disease

Combustion of pulverised coal compared to the lumpy coal (A) Provides better control of furnace temperature (B) Facilitates combustion with lower excess air (C) Provides higher thermal efficiency & flame temperature (D) All (A), (B) & (C)

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