Description : In a naturally aspirated diesel engine, the air is supplied by a A. supercharger B. centrifugal pump C. movement of engine piston D. reciprocating pump
Last Answer : ANSWER : C
Description : A reciprocating compressor is not suitable for use as a supercharger because: A. it runs at lower rpm B. the pressure ratio is high C. volumetric efficiency is high D. it is bulky and can handle small quantity of air
Last Answer : ANSWER : D
Description : Which of the following is the lightest and most volatile liquid fuel A. diesel B. kerosene C. fuel oil D. gasoline
Description : Which of the following is the lightest and most volatile liquid fuel? a. diesel b. kerosene c. gasoline d. fuel oil
Last Answer : ANSWER c. gasoline
Description : 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 ... /litre c) alcohol does not vaporize as easily as gasoline d) alcohols are corrosive in nature
Last Answer : Answer: a Explanation: Anti-knock characteristics of alcohol is good.
Description : Use of gasoline blend like tetraethyl lead in internal combustion engine a. increases the octane rating of the fuel b. allows engine to operate at higher compression ratio c. avoids auto-ignition of fuel d. all of the above
Last Answer : ANSWER d. all of the above
Description : Which of the following is compressed in a diesel engine cylinder A. air B. fuel C. air and fuel D. air and lub oil
Last Answer : ANSWER : A
Description : Which of the following medium is compressed in a diesel engine cylinder? a. air b. air and fuel c. air and lubricating oil d. fuel
Last Answer : ANSWER a. air
Description : A diesel engine is usually more efficient than a spark ignition engine because a. Diesel being a heavier hydrocarbon, release more heat per kg than gasoline b. The air standard efficiency of diesel ... an Spark ignition engine d.Self ignition temperature of diesel is higher than that of gasoline.
Last Answer : ANSWER c. The compression ratio of a diesel engine is higher than that of an S.I engine
Description : All heat engines utilize a. lower heating value of oil b. higher heating value of oil c. net calorific value of oil d. calorific value of fuel
Last Answer : ANSWER a. lower heating value of oil
Description : The self-ignition temperature of diesel oil compared to petrol is a. higher b. lower c. same d. depends on the quality of fuel
Last Answer : ANSWER a. higher
Description : In a 75 cc engine the parameter cc indicates a. fuel tank capacity b. lubricating oil capacity c. swept volume d. cylinder volume
Last Answer : ANSWER c. swept volume
Description : Octane number of gasoline is obtained by comparing the performance of the engine when running on a mixture of the following hydrocarbons A. ethane and methane B. normal heptane and iso-octane C. iso-heptane and octane D. iso-octane and TEL
Last Answer : ANSWER : B
Description : The molecular structure of the straight-run gasoline is changed by a) reforming b) refining c) cracking d) boiling
Last Answer : Answer: a Explanation: The molecular structure of the straight-run gasoline is changed by reforming and hydrocarbons are decomposed into smaller hydrocarbons by cracking.
Description : Small amount of gasoline is added to alcohol to a) reduce the emission b) to increase the power output c) to increase the efficiency d) to improve cold weather starting
Last Answer : Answer: d Explanation: None.
Description : Gasohol is a mixture of a) 90% ethanol + 10% gasoline b) 10% ethanol + 90% gasoline c) 40% ethanol + 60% gasoline d) 50% ethanol + 50% gasoline
Last Answer : Answer: b Explanation: 10% ethanol + 90% gasoline makes gashol.
Description : Air fuel ratio at which a petrol engine cannot work is A. 8:1 B. 12:1 C. 15:1 D. 20:1 and less
Description : Air fuel ratio for idling speed of a petrol engine is approximately A. 1:1 B. 5:1 C. 20:1 D. 10:1
Description : The theoretically correct air fuel ratio of a petrol engine is of the order of A. 6:1 B. 10:1 C. 15:1 D. 20:1
Description : The fuel air ratio in a petrol engine fitted with suction carburetor, operating with dirty air filter as compared to clean filter will be A. higher B. lower C. remain unaffected D. unpredictable
Description : In a simple carburetor, the air-fuel ratio increases when the A. density of air increases B. velocity of air increases C. velocity of air decreases D. density of air decreases
Description : Solid injection in CI engine means injection of A. solid fuel only B. liquid fuel only C. liquid fuel and air D. solid fuel and air
Description : In diesel engine the fuel injected would burn instantaneously at about compressed air temperature of A. 1000°C B. 250°C C. 450°C D. 2000°C
Description : The air-fuel ratio of the petrol engine is governed by A. fuel pump B. governor C. carburetor D. injector
Description : The output of a diesel engine can be increased without increasing the engine speed or size in the following way A. feeding more fuel B. increasing the flywheel size C. heating intake air D. supercharging
Description : In four stroke engine which of the following is also known as power stroke a. Suction stroke b. Compression stroke c. Expansion stroke d. Exhaust stroke (Ans:c) Measurements of fuel and air ... into IC engine,___________its efficiency A. increase B. decrease C. does not alter D. unpredictable on
Description : In _____________ injection system only one pump is sufficient for multi-cylinder engine. a) air b) mechanical c) compression fuel d) common rail
Description : Solid injection is also called ________________ a) air injection b) mechanical injection c) compression fuel injection d) none of the mentioned
Last Answer : Answer: b Explanation: Generally, solid injection is also called mechanical injection.
Description : The methods used on fuel injection are : a) air injection b) mechanical injection c) solid fuel injection d) all of the mentioned
Last Answer : Answer: d Explanation: The methods used on fuel injection are air injection, mechanical injection and solid fuel injection.
Description : 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
Last Answer : Answer: c Explanation: The air flow sensor, monitors mass or volume of air flowing into the intake manifold for adjusting the quantity of fuel while exhaust gas senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio.
Description : In _____________ sensor, output voltage changes in proportion to air-fuel ratio. a) engine temperature b) exhaust gas c) air flow d) air inlet temperature
Last Answer : Answer: b Explanation: Only in exhaust gas sensor, output voltage changes in proportion to air-fuel ratio.
Description : _____________ senor senses the amount of oxygen in the engine exhaust and calculates air-fuel ratio. a) Engine temperature b) Exhaust gas c) Air flow d) Air inlet temperature
Last Answer : Answer: b Explanation: Exhaust gas senor senses the amount of oxygen in the engine exhaust and calculates airfuel ratio while engine temperature sensor senses the temperature of the engine coolant, and from this data the computer adjusts the mixture strength to rich side for cold starting.
Description : The stoichiometric air fuel ration for petrol is 15:1 . What is the air fuel ratio required for maximum power? (a) 16:1 – 18:1 (b) 15:1 (c) 12:1 – 14:1 (d) 9:1 – 11:1
Last Answer : Ans :c
Description : If the performance of diesel engine of different sizes, cylinder dimensions and power rating are to be compared, which of the following parameters can be used for such comparison? (a) Swept volume (b) Air fuel ratio (c) Specific brake fuel consumption (d) Volumetric efficiency
Description : In a 4 S diesel engine, the term ‘squish’ refers to the (a) Injection of fuel in the precombustion chamber (b) Discharge of gases from the precombustion chamber (c) Entry of air into the combustion chamber (d) Stripping of fuel from the core
Description : 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
Last Answer : Ans :a
Description : Air fuel ratio at which a petrol engine cannot work is a. 8:1 b. 10:1 c. 20:1 and less d. 15:1
Last Answer : ANSWER c. 20:1 and less
Description : Mixing of air and fuel in the diesel engine occurs in a. injection pump b. carburetor c. engine cylinder d. inlet manifold
Last Answer : ANSWER c. engine cylinder
Description : The theoretically correct air fuel ratio for petrol engine is of the order of a.6 : 1 b. 9 : 1 c. 12 : 1 d. 15 : 1
Last Answer : Answer d. 15:1
Description : The air fuel ratio in petrol engines is controlled by a. valve opening / closing b. governing c. carburetion d. scavenging
Last Answer : ANSWER c. carburetion
Description : Supercharging is the process of a. supplying the engine with air at a density greater than the density of the surrounding atmosphere b. providing forced cooling air c. injecting excess fuel d. raising the exhaust pressure
Last Answer : ANSWER a. supplying the engine with air at a density greater than the density of the surrounding atmosphere
Description : In diesel engine, the fuel is ignited by a. spark b. injected fuel c. heat resulting from compressing air that is supplied for combustion d. ignitor
Last Answer : ANSWER c. heat resulting from compressing air that is supplied for combustion
Description : Rate of burning in the compression ignition engine can be controlled by a. rate of injection of fuel b. rate of air taken into carburetor c. both a. and b. d. none of the above
Last Answer : ANSWER a. rate of injection of fuel
Description : A supercharger is used in the engines of earthmoving machines at higher altitudes because (a) The ambient atmospheric pressure is less at higher altitudes (b) Four-cycle engines depend on the suction ... rugged enough for higher altitude (d) The ambient temperature is less as the altitude is higher
Last Answer : (a) The ambient atmospheric pressure is less at higher altitudes
Description : The reason for supercharging in any engine is to be A. increase efficiency B. increase power C. effect fuel economy D. reduce weight and bulk for a given output
Description : HUCR is the highest compression ratio at which the A. engine can be run B. engine gives maximum output C. engine is most efficient D. fuel can be used in a test engine without detonation
Description : In a carburetor the level of the fuel in the float chamber as compared to the level of the main jet in the venture is A. lower B. same C. higher D. same or higher
Description : Motoring test is conducted on IC engines to determine A. brake power B. indicated power C. friction power D. fuel consumption at full load
Description : The specific fuel consumption of a petrol engine compared to diesel engine of same H.P is A. same B.more C. less D. unpredictable
Description : A 100 cc engine has thefollowingparameter as 100 cc A. fuel tankcapacity B. sweptvolume C. luboilcapacity D. clearence volumen