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
Last Answer : Ans :c
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 : In compression ignition (CI) engine, the compression ratio is a. Cylinder volume / Clearance volume b. Swept Volume / Cylinder Volume c. Clearance volume / Cylinder volume d. Cylinder volume / Swept volume (Ans:a)
Last Answer : In two stroke engine there is one power stroke in _____ of crankshaft rotation. a. 90° b. 180° c. 270° d. 360° (Ans:d)
Description : 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 ... kg of air is a. 879.1 kJ/ b. 890.2 kJ c. 895.3 kJ d. 973.5 kJ
Last Answer : ANSWER d. 973.5 kJ
Description : The volume of air delivered by the compressor is called A. Free air delivery B. Compressor capacity C. Swept volume D. Mean effective pressure
Last Answer : ANSWER : B
Description : For an engine operating on air standard Otto cycle, the clearance volume is 10% of the swept volume. The specific heat ratio of air is 1.4. The air standard cycle efficiency is a. 38.3 % b. 39.8 % c. 60.2 % d. 61.7 %
Last Answer : ANSWER d. 61.7%
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 : A 100 cc engine has thefollowingparameter as 100 cc A. fuel tankcapacity B. sweptvolume C. luboilcapacity D. clearence volumen
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
Description : In a morse test for a 2 cylinder, 2 S SI engine, the brake power was 9 kW. Whereas the brake power of individual cylinders with spark cut off were 4.25 kW and 3.75 kW. The mecheffic of the engine is (a) 90% (b) 80% (c) 45.5% (d) 52.5%
Last Answer : Ans :a
Description : Clearance volume in compressor should be A. As large as possible B. As small as possible C. About 50% of swept volume D. About 100% of swept volume
Description : If one cylinder of a diesel engine receives more fuel than others , then for that cylinder the A. exhaust will be smoky B. scavenging occurs C. exhaust temperature will be high D. engine starts overheating
Description : In _____________ injection system only one pump is sufficient for multi-cylinder engine. a) air b) mechanical c) compression fuel d) common rail
Last Answer : Answer: d Explanation: None.
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 : An engine indicator is used to determine the following A. Speed B. Temperature C. M.E.P D. Volume of cylinder
Last Answer : ANSWER : C
Description : An engine indicator is used to determine the following a. Speed. b. Temperature. c. Volume of cylinder. d. Mean effective pressure and Indicated horse power.
Last Answer : ANSWER d. Mean effective pressure and Indicated horse power.
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 : As a result of detonation in an I.C engine, following parameter attains a high value A. peak temperature B. peak pressure C. rate of pressure rise D. rate of temperature rise
Description : Fuel is injected into the cylinder at the end of ______________ stroke. a) suction b) compression c) expansion d) exhaust
Last Answer : Answer: b Explanation: Fuel is injected into the cylinder at the end of compression stroke and not at suction or expansion stroke.
Description : The mean effective pressure obtained from the engine indicator indicates the a. maximum pressure developed b. instantaneous pressure c. exhaust pressure d. average pressure
Last Answer : ANSWER d. average pressure
Description : Ignition timing of a multi-cylinder SI engine can be adjusted by A. rotating the cam shaft B. adjusting the generator pulley C. rotating the distributor D. adjusting the pump pulley
Description : Morse test is conducted on the engine to calculate the mechanical efficiency of A. single cylinder CI engine B. single cylinder SI engine C. only on two stroke engines D. multi cylinder engine
Last Answer : ANSWER : D
Description : A two stroke engine has a speed of 750 rpm. A four stroke engine having an identical cylinder size runs at 1500 rpm. The theoretical output of the two stroke engine will (a) Be twice that of the four stroke ... ) Be the same as that of the four stoke (d) Depend upon whether it is a CI or SI engine
Description : The method of determination of indicated power of multi cylinder SI engine is by use of (a) Morse test (b) Prony brake test (c) Motoring test (d) Heat balance test
Last Answer : Ans : a
Description : The most popular firing order in a 4-cylinder inline internal combustion engine is a. 1-2-3-4 b. 1-3-2-4 c. 1-3-4-2 d. 1-2-4-3
Last Answer : ANSWER b. 1-3-4-2
Description : The maximum temperature in the I.C engine cylinder is of the order of a. 500 – 1000 C b. 1000 – 1500 C c. 1500 – 2000 C d. 2000 – 2500 C
Last Answer : ANSWER d. 2000 – 2500 C
Description : Scavenging air in diesel engine means a. air used for combustion under pressure b. forced air for cooling the cylinder c. burnt air containing products of combustion d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke
Last Answer : ANSWER d. air used for forcing burnt gases out of the engines cylinder during the exhaust stroke
Description : A knocking sound is produced in the engine when the fuel (a) Burns fast (b) contains lubricating oil (c) Burns slow (d) contains water
Last Answer : Burns fast
Description : For a reciprocating pump, the indicator diagram is the graph between the (A) Discharge and overall efficiency (B) Volume swept by piston for one complete revolution and the pressure in the cylinder (C) Angle swept by the crank pin at any instant and the discharge (D) None of these
Last Answer : (B) Volume swept by piston for one complete revolution and the pressure in the cylinder
Description : The accumulation of carbon in a cylinder results in increase of A. clearance volume B. volumetric efficiency C. ignition time D. effective compression ratio
Description : The accumulation of carbon in a cylinder results in increase of a. clearance volume b. volumetric efficiency c. ignition time d. effective compression ratio
Last Answer : ANSWER d. effective compression ratio
Description : What is the formula for compression (rk) ratio of the Otto cycle? a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression b. rk = Volume of cylinder ... c. rk = Volume of cylinder at the end of compression / clearance volume d. none of the above
Last Answer : ANSWER a. rk = Volume of cylinder at the beginning of compression / Volume of cylinder at the end of compression
Description : A fuel of an octane number rating of 75 matches in knocking intensity as a mixture of a) 75% iso-octane and 25% normal heptane b) 75% normal heptane and 25% iso-octane c) 75% petrol and 25% diesel d) 75% diesel and 25% petrol
Last Answer : Answer: a Explanation: None.
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 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 : 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 : 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 : 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 : 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 : 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 : The specific fuel consumption for diesel engine is approximately A. 0.15 kg/kWh B. 0.2 kg/kWh C. 28 kg/kWh D. 0.36 kg/kWh
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 _____________ 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 : Disadvantage of hydrogen as a fuel in IC engine is a) storage is safe b) low NOx c) detonating tendency d) easy handling
Last Answer : Answer: c Explanation: None.
Description : An engine produces 10 kW brake power while working with a brake thermal efficiency of 30%. If the calorific value of the fuel used is 40000 kJ/kg, then what is the fuel consumption? (a) 1.5 kg/hour (b) 3 kg/hour (c) 0.3 kg/hour (d) 1 kg/hour
Last Answer : Ans :b