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
Last Answer : ANSWER : C
Description : State the functions following ignition system components (i) Ignition coil (ii) Distributor (iii)Condenser (iv)Spark plug
Last Answer : Functions following ignition system components: (i) Ignition coil: Ignition coil receives voltage from primary circuit and convert it to very high voltage up to 28000 volts required for spark by means of ... Charge of air and petrol is ignited by means of the spark produced by spark plug.
Description : In a battery ignition system, the intensity of spark is A. minimum at low engine speed B. minimum at low engine speed and increases with engine speed C. maximum al low engine speed and decreases with engine speed D. maximum at low engine speed
Description : The compression ratio in a Spark Ignition (SI) engine is generally in between a. 7 to 10 b. 10 to 14 c. 14 to 18 d. 18 to 22 (Ans:a)
Last Answer : Which of the following is not true for two stroke engine as compared to four stroke engine? a. Less cooling is required b. Greater lubrication is required c. More uniform torque on crankshaft d. Complete exhaust of products of combustion (Ans:a)
Description : The knocking in spark ignition engines can be reduced by a. Retarding the spark. b. Increasing the engine speed. c. Both a and b d. None of these.
Last Answer : ANSWER c. Both a and b.
Description : Which of the following engine can work on very lean mixture a. Spark ignition engine b. compression ignition engine c. two stroke engine d. Four stroke engine
Last Answer : ANSWER b. compression ignition engine
Description : The knocking in spark ignition engines can be reduced by a. Retarding the spark. b. Increasing the engine speed. c. Both a and b. d. None of these.
Last Answer : ANSWER c. Both a and b
Description : For spark ignition engine, the equivalence ratio of mixture entering the combustion chamber has values (A) for idling and for peak power conditions (B) for both idling and peak power conditions (C) for idling and for peak power conditions (D) for both idling and peak power conditions
Last Answer : ANSWER (B) for both idling and peak power conditions
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 : Which of the following cycle is used for Spark Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle
Last Answer : Answer a. Otto cycle
Description : The air-fuel ratio of the petrol engine is governed by A. fuel pump B. governor C. carburetor D. injector
Description : A spark plug is used in a. petrol engine b. diesel engine c. gas engine d. steam engine
Last Answer : ANSWER a. petrol engine
Description : _______________ is used to enable cold starting, with out the use of a heater plug. a) Pintaux nozzle b) Multi hole injector c) Long stem injector d) Pintle nozzle
Last Answer : Answer: a Explanation: Generally, intaux nozzle is used to enable cold starting, with out the use of a heater plug.
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
Last Answer : ANSWER : D
Description : The output of a diesel engine can be increased without increasing the engine size in following way a. injecting more fuel b. increasing flywheel size c. scavenging d. supercharging
Last Answer : ANSWER d. supercharging
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 : In spark ignition engines, the knocking tendency can be decreased by a) decreasing compression ratio b) controlling intake throttle c) controlling ignition timing d) adding dopes like tetraethyl lead and ethylene dibromide
Last Answer : Answer: d Explanation: None.
Description : The tendency of knocking in CI engine reduces by (a) High self ignition temperature of fuel (b) Decrease in jacket water temperature (c) Injection of fuel just before TDC (d) Decrease in injection pressure
Last Answer : Ans :c
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 : 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 : The compression ratio cannot be increased beyond certain limit as it results in a. auto-ignition of fuel b. detonation c. engine knocking d. all the above
Last Answer : ANSWER d. all the above
Description : Spark plug is provided in a/an (A) Engine having carburettor (B) Diesel engine (C) Compression ignition engine (D) Both (B) & (C)
Last Answer : (A) Engine having carburettor
Description : The sparking voltage of the spark plug is A. 6 to 12 V B. 100 to 450 V C. 1 to 2 kV D. 20 to 30kV
Description : iesel engine has less reserve torque then spark ignition because ∙ Torque-speed curve is governed by volumetric efficiency of fuel pump and engine cylinder ∙ Torque is a function of thermal efficiency ∙ Diesel engine has generally low speed engine ∙ None of the above
Last Answer : ∙ Torque is a function of thermal efficiency
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 : The tendency of a petrol engine to knock increases by a. supercharging b. scavenging c. increasing the engine horse power d. reducing the spark advance
Last Answer : ANSWER a. supercharging
Description : A fuel of cetane number 40 has the same ignition quality as a mixture of a) 40% cetane and 60% alpha methyl naphthalene b) 40% alpha methyl naphthalene and 60% cetane c) 40% petrol and 60% diesel d) 40% diesel and 60% petrol
Last Answer : Answer: a Explanation: A fuel of cetane number 40 has the same ignition quality as a mixture of 40% cetane and 60% alpha methyl naphthalene as cetane number is counted on cetane percentage.
Description : By higher octane number of SI fuel, it is meant that the fuel has (a) Higher heating value (b) Higher flash point (c) Lower volatility (d) Longer ignition delay
Last Answer : Ans : d
Description : Cetane number is a measure of a. ignition quality b. addition in fuel c. calorific value of fuel d. viscosity of the fuel
Last Answer : ANSWER a. ignition quality
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 pre-chamber and swirl type of combustion system ______________ is used. a) single hole injector b) multi hole injector c) long stem injector d) pintle nozzle
Last Answer : Answer: d Explanation: In pre-chamber and swirl type of combustion system pintle nozzle is used and not the other nozzles.
Description : The usual types of diesel injectors are : a) single hole injector b) multi hole injector c) long stem injector d) all of the mentioned
Last Answer : Answer: d Explanation: The types of diesel injectors are single hole injector, multi hole injector and long stem injector.
Description : The knock in diesel engine occurs due to A. instantaneous and rapid burning of the first part of the charge B. instantaneous auto ignition of the last part of the charge C. delayed burning of the last part of the charge D. reduction of delay period
Last Answer : ANSWER : A
Description : Most high speed compression ignition engine operate on A. dual cycle B. otto cycle C. diesel cycle D.Carnot cycle
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 : Combustion in compression ignition engine is a. homogeneous b. heterogeneous c. laminar d. turbulent
Last Answer : ANSWER b. heterogeneous
Description : Which of the following cycle is used for Compression Ignition engine? a. Otto cycle b. Diesel cycle c. Dual cycle d. Carnot cycle
Last Answer : Answer b. Diesel cycle
Description : When a vehicle passes, TV reception gets distorted. This is because – (1) metal reflects radiowaves (2) spark plug creates electromagnetic disturbances (3) vehicle pollution affects the performance of the TV components (4) modern vehicles use electro ignition system
Last Answer : (2) spark plug creates electromagnetic disturbances Explanation: This is caused due to the interference caused by the electromagnetic waves generated by a passing vehicle. These waves were within the same ... in which two waves superimpose to form a resultant wave of greater or lower amplitude.
Description : With increase in __________ Knocking tendency in a spark ignition petrol engine decreases. (A) Supercharging (B) Wall temperature (C) Compression ratio (D) Engine speed
Last Answer : Option D
Description : Air-petrol ratio for maximum power generation in spark ignition engine is about (A) 6 : 1 (B) 12 : 1 (C) 18 : 1
Last Answer : Option B
Description : The violent noises heard in an engine during the process of combustion after the position has passed over the top dead center is known as? 1. Stationary 2. Spark ignition 3. Detonation 4. all of these
Last Answer : <!-- [endif] -->ans 3
Description : Which of the following types of internal combustion engine is generally used as portable engine for pumping and electricity generation? 1. Spark ignition 2. Stationary 3. Vertical single cylinder 3. all of these
Last Answer : ans 2
Description : The critical spark energy required to ignite a given mixture A. decreases with decreasing sparking voltage B. increases with decreasing sparking voltage C. increases with increasing sparking voltage D. decreases with increasing sparking voltage
Description : In a cycle the spark lasts roughly for A. 1 sec B. 0.1 sec C. 0.0001 sec D.001 sec
Description : In SI engines knocking can be reduced by (a) Increasing the compression ratio (b) Increasing the cooling water temperature (c) Retarding the spark advance (d) Increasing the inlet air temperature
Description : Detonation can be controlled by a. varying the compression ratio b. using lean mixture c. retarding the spark timing d. reducing the rpm
Last Answer : ANSWER c. retarding the spark timing
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