In a coil ignition system of petrol engines, a condenser is connected across the contact-breaker in order to

prevent sparking across the gap between the points

cause more rapid break of the primary current, giving a higher voltage in the secondary circuit

In a four stroke cycle petrol engine, , the compression

starts at 40° before bottom dead centre and ends at 30° after bottom dead centre

starts at 40° after bottom dead centre and ends at 30° before top dead centre

starts at 40° before bottom dead centre and ends at 30° after bottom dead centre

starts at bottom dead centre and ends at top dead centre

In a four stroke engine, the working cycle is completed in

three revolutions of the crankshaft

one revolution of the crankshaft

two revolutions of the crankshaft

three revolutions of the crankshaft

four revolutions of the crankshaft

The basic requirement of a good combustion chamber is

high thermal efficiency and power output

when thorium is irradiated by neutrons

A carburettor is used to supply

petrol, air and lubricating oil

Pre-ignition is caused by the spontantaneous combustion of the mixture before the end of the compression stroke, and is due to

red hot carbon deposits on cylinder walls

102 + Mcqs in IC Engines and Nuclear Power Plants in Automobile Engineering Page 2 McqOptions

51.	Lubrication in I.C. engines dissipates the heat generated from the moving parts due to friction.
A.	True
B.	False
Answer» B. False

Discussion

52.	A supercharger receives air from the atmosphere surrounding the engine, compresses it to a higher pressure and then feeds it into the inlet valve of the engine.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

53.	The increase in intake temperature of internal combustion engines will __________ efficiency.
A.	have no effect on
B.	increase
C.	decrease
Answer» D.

Discussion

54.	Supercharging is the process of supplying the intake air to the engine cylinder at a density __________ the density of the surrounding atmosphere.
A.	equal to
B.	less than
C.	greater than
Answer» D.

Discussion

55.	The injection of fuel by external source is not required in case of engines working on Otto cycle.
A.	Yes
B.	No
Answer» B. No

Discussion

56.	An ignition coil in the spark ignition engines supplies __________ voltage to the spark plug.
A.	high
B.	low
Answer» B. low

Discussion

57.	In a coil ignition system of petrol engines, a condenser is connected across the contact-breaker in order to
A.	prevent sparking across the gap between the points
B.	cause more rapid break of the primary current, giving a higher voltage in the secondary circuit
C.	both (a) and (b)
D.	none of the above
Answer» D. none of the above

Discussion

58.	The running cost of a petrol engine is __________ than that of a diesel engine.
A.	higher
B.	lower
Answer» B. lower

Discussion

59.	The thermal efficiency of a petrol engine is __________ as compared to diesel engine.
A.	same
B.	less
C.	more
Answer» C. more

Discussion

60.	The compression ratio in petrol engines is kept low as compared to diesel engines because higher compression ratio in petrol engines would lead to pre-ignition of fuel.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

61.	The __________ engines can work on very lean mixture of fuel.
A.	spark ignition
B.	compression ignition
Answer» C.

Discussion

62.	The cylinder of a gas engine is made __________ than that of the petrol engine.
A.	smaller
B.	larger
Answer» C.

Discussion

63.	For the same maximum pressure and heat input, the exhaust temperature of petrol engine is __________ than that of diesel engine.
A.	less
B.	more
Answer» C.

Discussion

64.	A diesel engine has inlet valve, fuel injection valve and exhaust valve.
A.	Yes
B.	No
Answer» B. No

Discussion

65.	The diesel engines are also known as __________ engines.
A.	compression ignition
B.	spark ignition
Answer» B. spark ignition

Discussion

66.	In diesel engines, the ignition takes place due to the heat produced in the engine cylinder at the end of compression.
A.	Correct
B.	Incorrect
Answer» B. Incorrect

Discussion

67.	The petrol engines are also known as __________ engines.
A.	compression ignition
B.	spark ignition
Answer» C.

Discussion

68.	The sparking in a petrol engine increases pressure and temperature of the products of combustion, but the volume remains constant.
A.	Yes
B.	No
Answer» B. No

Discussion

69.	During idling, a petrol engine requires __________ mixture.
A.	lean
B.	rich
C.	chemically correct
Answer» C. chemically correct

Discussion

70.	During suction stroke of a four stroke petrol engine, the inlet valve opens and the charge is sucked into the cylinder as the piston moves upwards from the bottom dead centre.
A.	True
B.	False
Answer» C.

Discussion

71.	In a petrol engine, the charge is ignited with the help of a spark plug.
A.	Yes
B.	No
Answer» B. No

Discussion

72.	In a four stroke cycle petrol engine, , the compression
A.	starts at 40° after bottom dead centre and ends at 30° before top dead centre
B.	starts at 40° before bottom dead centre and ends at 30° after bottom dead centre
C.	starts at bottom dead centre and ends at top dead centre
D.	may start and end anywhere
Answer» B. starts at 40° before bottom dead centre and ends at 30° after bottom dead centre

Discussion

73.	Thermal efficiency of a two stroke cycle engine is __________ a four stroke cycle engine.
A.	equal to
B.	less than
C.	greater than
Answer» C. greater than

Discussion

74.	The two stroke cycle engines have lighter flywheel.
A.	Agree
B.	Disagree
Answer» B. Disagree

Discussion

75.	A two stroke cycle engine gives __________ mechanical efficiency than a four stroke cycle engine.
A.	higher
B.	lower
Answer» B. lower

Discussion

76.	A two stroke cycle engine gives __________ the number of power strokes as compared to the four stroke cycle engine, at the same engine speed.
A.	half
B.	same
C.	double
D.	four times
Answer» D. four times

Discussion

77.	In a four stroke engine, the working cycle is completed in
A.	one revolution of the crankshaft
B.	two revolutions of the crankshaft
C.	three revolutions of the crankshaft
D.	four revolutions of the crankshaft
Answer» C. three revolutions of the crankshaft

Discussion

78.	The engines in which the combustion of fuel takes place inside the engine cylinder are called internal combustion engines.
A.	True
B.	False
Answer» B. False

Discussion

79.	The secondary fuel used in nuclear power plants is
A.	U 233 and Pu 239
B.	U 235 and Th 232
C.	U 235 and Pu 238
D.	U 233 and Pu 238
Answer» B. U 235 and Th 232

Discussion

80.	In nuclear power plants, due to reflector, less fuel is needed to generate sufficient neutrons to sustain a chain reaction.
A.	Yes
B.	No
C.	-
D.	-
Answer» B. No

Discussion

81.	The nuclear power station at Tarapur has the reactor of the __________ type.
A.	pressurized water
B.	boiling water
C.	gas cooled
D.	liquid metal cooled
Answer» C. gas cooled

Discussion

82.	High speed compression engines operate on
A.	Otto cycle
B.	Diesel cycle
C.	Dual-combustion cycle
D.	all of these
Answer» D. all of these

Discussion

83.	In a four stroke cycle petrol engine, the charge is compressed when both the valves (i.e. inlet valve and exit valve) are closed,
A.	Agree
B.	Disagree
C.	-
D.	-
Answer» B. Disagree

Discussion

84.	The basic requirement of a good combustion chamber is
A.	minimum turbulence
B.	low compression ratio
C.	high thermal efficiency and power output
D.	low volumetric efficiency
Answer» D. low volumetric efficiency

Discussion

85.	Morse test can be conducted for
A.	petrol engines
B.	diesel engines
C.	multi-cylinder engines
D.	all of these
Answer» D. all of these

Discussion

86.	The energy released during the fission of one atom of Uranium - 235 in million electron volts is about
A.	100
B.	200
C.	300
D.	400
Answer» C. 300

Discussion

87.	The pre-ignition occurs before the spark is produced whereas detonation develops after the introduction of spark.
A.	Agree
B.	Disagree
C.	-
D.	-
Answer» B. Disagree

Discussion

88.	The detonation is also called knocking or pinking.
A.	Yes
B.	No
C.	-
D.	-
Answer» B. No

Discussion

89.	U 233 is produced
A.	artificially
B.	as basic raw material
C.	when thorium is irradiated by neutrons
D.	by fission of U 238
Answer» D. by fission of U 238

Discussion

90.	A carburettor is used to supply
A.	petrol, air and lubricating oil
B.	air and diesel
C.	petrol and lubricating oil
D.	petrol and air
Answer» E.

Discussion

91.	The increase of cooling water temperature in petrol engine will __________ the knocking tendency.
A.	not effect
B.	decrease
C.	increase
D.	-
Answer» D. -

Discussion

92.	The pressure inside the cylinder is __________ the atmospheric pressure during the exhaust stroke.
A.	equal to
B.	below
C.	above
D.	-
Answer» D. -

Discussion

93.	The self ignition temperature of petrol is __________ as compared to diesel oil.
A.	same
B.	lower
C.	higher
D.	-
Answer» D. -

Discussion

94.	Ordinary water is sometimes used as moderator when enriched uranium is used as a fuel in nuclear power plants.
A.	Yes
B.	No
C.	-
D.	-
Answer» B. No

Discussion

95.	In petrol engine, using a fixed octane rating fuel and fixed compression ratio, supercharging will __________ the knocking tendency.
A.	not effect
B.	decrease
C.	increase
D.	-
Answer» D. -

Discussion

96.	Each fission of U 235 produces on the average __________ fast neutrons as a product of reaction.
A.	2.46
B.	24.6
C.	246
D.	2460
Answer» B. 24.6

Discussion

97.	The detonating tendency in petrol engines increases with increase of compression ratio.
A.	True
B.	False
C.	-
D.	-
Answer» B. False

Discussion

98.	In open combustion chamber in diesel engines, the shape and layout of the piston crown, the inlet port and the valve produce the turbulent effect of fuel mixture.
A.	True
B.	False
C.	-
D.	-
Answer» B. False

Discussion

99.	Pre-ignition is caused by the spontantaneous combustion of the mixture before the end of the compression stroke, and is due to
A.	cylinder walls being too hot
B.	overheated spark plug points
C.	red hot carbon deposits on cylinder walls
D.	any one of these
Answer» E.

Discussion

100.	In diesel engines, the fuel is injected in the form of very fine spray, into the engine cylinder, which gets ignited due to high temperature of the compressed air.
A.	Agree
B.	Disagree
C.	-
D.	-
Answer» B. Disagree

Discussion

Explore topic-wise MCQs in Automobile Engineering.

Lubrication in I.C. engines dissipates the heat generated from the moving parts due to friction.

A supercharger receives air from the atmosphere surrounding the engine, compresses it to a higher pressure and then feeds it into the inlet valve of the engine.

The increase in intake temperature of internal combustion engines will __________ efficiency.

Supercharging is the process of supplying the intake air to the engine cylinder at a density __________ the density of the surrounding atmosphere.

The injection of fuel by external source is not required in case of engines working on Otto cycle.

An ignition coil in the spark ignition engines supplies __________ voltage to the spark plug.

In a coil ignition system of petrol engines, a condenser is connected across the contact-breaker in order to

The running cost of a petrol engine is __________ than that of a diesel engine.

The thermal efficiency of a petrol engine is __________ as compared to diesel engine.

The compression ratio in petrol engines is kept low as compared to diesel engines because higher compression ratio in petrol engines would lead to pre-ignition of fuel.

The __________ engines can work on very lean mixture of fuel.

The cylinder of a gas engine is made __________ than that of the petrol engine.

For the same maximum pressure and heat input, the exhaust temperature of petrol engine is __________ than that of diesel engine.

A diesel engine has inlet valve, fuel injection valve and exhaust valve.

The diesel engines are also known as __________ engines.

In diesel engines, the ignition takes place due to the heat produced in the engine cylinder at the end of compression.

The petrol engines are also known as __________ engines.

The sparking in a petrol engine increases pressure and temperature of the products of combustion, but the volume remains constant.

During idling, a petrol engine requires __________ mixture.

During suction stroke of a four stroke petrol engine, the inlet valve opens and the charge is sucked into the cylinder as the piston moves upwards from the bottom dead centre.

In a petrol engine, the charge is ignited with the help of a spark plug.

In a four stroke cycle petrol engine, , the compression

Thermal efficiency of a two stroke cycle engine is __________ a four stroke cycle engine.

The two stroke cycle engines have lighter flywheel.

A two stroke cycle engine gives __________ mechanical efficiency than a four stroke cycle engine.

A two stroke cycle engine gives __________ the number of power strokes as compared to the four stroke cycle engine, at the same engine speed.

In a four stroke engine, the working cycle is completed in

The engines in which the combustion of fuel takes place inside the engine cylinder are called internal combustion engines.

The secondary fuel used in nuclear power plants is

In nuclear power plants, due to reflector, less fuel is needed to generate sufficient neutrons to sustain a chain reaction.

The nuclear power station at Tarapur has the reactor of the __________ type.

High speed compression engines operate on

In a four stroke cycle petrol engine, the charge is compressed when both the valves (i.e. inlet valve and exit valve) are closed,

The basic requirement of a good combustion chamber is

Morse test can be conducted for

The energy released during the fission of one atom of Uranium - 235 in million electron volts is about

The pre-ignition occurs before the spark is produced whereas detonation develops after the introduction of spark.

The detonation is also called knocking or pinking.

U 233 is produced

A carburettor is used to supply

The increase of cooling water temperature in petrol engine will __________ the knocking tendency.

The pressure inside the cylinder is __________ the atmospheric pressure during the exhaust stroke.

The self ignition temperature of petrol is __________ as compared to diesel oil.

Ordinary water is sometimes used as moderator when enriched uranium is used as a fuel in nuclear power plants.

In petrol engine, using a fixed octane rating fuel and fixed compression ratio, supercharging will __________ the knocking tendency.

Each fission of U 235 produces on the average __________ fast neutrons as a product of reaction.

The detonating tendency in petrol engines increases with increase of compression ratio.

In open combustion chamber in diesel engines, the shape and layout of the piston crown, the inlet port and the valve produce the turbulent effect of fuel mixture.

Pre-ignition is caused by the spontantaneous combustion of the mixture before the end of the compression stroke, and is due to

In diesel engines, the fuel is injected in the form of very fine spray, into the engine cylinder, which gets ignited due to high temperature of the compressed air.