Question 1

The advantages of the indirect injection combustion chambers are

Accepted Answer

A) low injection pressure 
B) direction of spray is not critical 
C) both (a) and (b) 
D) good cold starting performance 
A) low injection pressure 
B) direction of spray is not critical 
C) both (a) and (b) 
D) good cold starting performance C

Question 2

Compression loss in I.C engines occurs duto

Accepted Answer

A) leaking piston rings 
B) use of thick head gasket 
C) clogged air-inlet slots 
D) all of the above. 
A) leaking piston rings 
B) use of thick head gasket 
C) clogged air-inlet slots 
D) all of the above. D

Question 3

The accumulation of carbon in a cylinder results in increase of

Accepted Answer

A) clearance volume 
B) volumetric efficiency 
C) ignition time 
D) effective compression ratio 
A) clearance volume 
B) volumetric efficiency 
C) ignition time 
D) effective compression ratio D

Question 4

In CI engines with increase in compression ratio the delay period

Accepted Answer

A) increases 
B) decreases 
C) first increases and then decreases 
D) not affected 
A) increases 
B) decreases 
C) first increases and then decreases 
D) not affected

Question 5

Decreasing the cooling water temperature in SI engines the knocking tendency

Accepted Answer

A) increases 
B) decreases 
C) not affected 
D) none of the above 
A) increases 
B) decreases 
C) not affected 
D) none of the above

Question 6

The precess of breaking up or a liquid into fine droplets by spraying is called

Accepted Answer

A) vaporisation 
B) carburetion 
C) ionisation 
D) atomisation. 
A) vaporisation 
B) carburetion 
C) ionisation 
D) atomisation.

Question 7

Excess quantities of sulphur in diesel fuel are Objectionable because it may cause the following

Accepted Answer

A) piston ring and cylinder wear 
B) formation of hard coating on piston skirts 
C) oil sludge in the engine crank case 
D) detonation 
A) piston ring and cylinder wear 
B) formation of hard coating on piston skirts 
C) oil sludge in the engine crank case 
D) detonation

Question 8

with increase in compression ratio flame speed

Accepted Answer

A) increases 
B) decreases 
C) remains the same 
D) none of the above 
A) increases 
B) decreases 
C) remains the same 
D) none of the above

Question 9

Open combustion chambers in CI engines require

Accepted Answer

A) high injection pressures 
B) accurate metering of fuel by the injection system 
C) both (a) and (b) 
D) none of the above 
A) high injection pressures 
B) accurate metering of fuel by the injection system 
C) both (a) and (b) 
D) none of the above

Question 10

In a cycle, the spark lasts roughly for

Accepted Answer

A) 1 sec 
B) 0.1 sec 
C) 0.01 sec 
D) 0.001 sec 
A) 1 sec 
B) 0.1 sec 
C) 0.01 sec 
D) 0.001 sec

Question 11

It the temperature of intake air in IC engines is lowered, then its efficiency will

Accepted Answer

A) increase 
B) decrease 
C) remain same 
D) increase upto certain limit and then decrease 
A) increase 
B) decrease 
C) remain same 
D) increase upto certain limit and then decrease

Question 12

Which of the following statements is correct?

Accepted Answer

A) All the irreversible engines have same efficiency 
B) All the reversible engines have same efficiency 
C) Both Rankine and Caront cycles have same efficiency between same temperature limits 
D) All reversible engines working between same temperature limits have same-efficiency 
A) All the irreversible engines have same efficiency 
B) All the reversible engines have same efficiency 
C) Both Rankine and Caront cycles have same efficiency between same temperature limits 
D) All reversible engines working between same temperature limits have same-efficiency

Question 13

Desirable characteristics of the combustion chamber for SI engines to avoid knock is

Accepted Answer

A) small bore 
B) short ratio of fame path to bore 
C) absence of hot surfaces in the last region of the charge 
D) all of the above 
A) small bore 
B) short ratio of fame path to bore 
C) absence of hot surfaces in the last region of the charge 
D) all of the above

Question 14

Increasing the compression ratio in SI engines the knocking tendency

Accepted Answer

A) decreases 
B) increases 
C) not affected 
D) none of the above 
A) decreases 
B) increases 
C) not affected 
D) none of the above

Question 15

In CI engines the delay period is affected by

Accepted Answer

A) compression ratio 
B) engine speed 
C) output 
D) all of the above 
A) compression ratio 
B) engine speed 
C) output 
D) all of the above

Question 16

Detonation in SI engines occur due to

Accepted Answer

A) pre ignition of the charge before the spark 
B) sudden ignition of the charge before the spark 
C) autoignition of the charge after the spark in struck 
D) none of the above 
A) pre ignition of the charge before the spark 
B) sudden ignition of the charge before the spark 
C) autoignition of the charge after the spark in struck 
D) none of the above

Question 17

A high flame speed is obtained in diesel engine when air fuel ratio is

Accepted Answer

A) uniform throughout the mixture 
B) chemically correct mixture 
C) about 3-5% rich mixture 
D) about 10% rich mixture 
A) uniform throughout the mixture 
B) chemically correct mixture 
C) about 3-5% rich mixture 
D) about 10% rich mixture

Question 18

In CI engines knocking tendency increases with

Accepted Answer

A) increase in compression ratio 
B) increasing inlet temperature of air 
C) decrease in compression ratio 
D) increasing coolant water temperature 
A) increase in compression ratio 
B) increasing inlet temperature of air 
C) decrease in compression ratio 
D) increasing coolant water temperature

Question 19

Crankcase explosion in I.C. engines usually occurs as

Accepted Answer

A) first a mild explosion followed by a bi explosion 
B) first a big explosion followed by a mil explosion 
C) both mild and big explosions occi simultaneously 
D) never occurs 
A) first a mild explosion followed by a bi explosion 
B) first a big explosion followed by a mil explosion 
C) both mild and big explosions occi simultaneously 
D) never occurs

Question 20

In diesel engine the diesel fuel injected intc cylinder would burn instantly at about compressed air temperature of

Accepted Answer

A) 250°C 
B) 500°C 
C) 1000°C 
D) 150CPC 
A) 250°C 
B) 500°C 
C) 1000°C 
D) 150CPC

The advantages of the indirect injection combustion chambers are

Compression loss in I.C engines occurs duto

The accumulation of carbon in a cylinder results in increase of

In CI engines with increase in compression ratio the delay period

Decreasing the cooling water temperature in SI engines the knocking tendency

The precess of breaking up or a liquid into fine droplets by spraying is called

Excess quantities of sulphur in diesel fuel are Objectionable because it may cause the following

with increase in compression ratio flame speed

Open combustion chambers in CI engines require

In a cycle, the spark lasts roughly for

It the temperature of intake air in IC engines is lowered, then its efficiency will

Which of the following statements is correct?

Desirable characteristics of the combustion chamber for SI engines to avoid knock is

Increasing the compression ratio in SI engines the knocking tendency

In CI engines the delay period is affected by

Detonation in SI engines occur due to

A high flame speed is obtained in diesel engine when air fuel ratio is

In CI engines knocking tendency increases with

Crankcase explosion in I.C. engines usually occurs as

In diesel engine the diesel fuel injected intc cylinder would burn instantly at about compressed air temperature of

Internal Combustion Engines and Their Advantages and Disadvantages

Diesel Engines and Thermodynamic Cycles

Combustion and Efficiency in Engines

Fuel and Hydrocarbon

Automobile Engine Fuel Systems

Fuel Injection and Ignition Systems in Automotive Engineering

Supercharging and Ignition Timing in Engines

Automotive Engine Lubrication and Cooling System

Engine Cooling, Efficiency, and Emissions

Exhaust Emissions and Control Systems in Vehicles

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Exam 8: Combustion and Engine Performance in IC Engines

The advantages of the indirect injection combustion chambers are

Compression loss in I.C engines occurs duto

The accumulation of carbon in a cylinder results in increase of

In CI engines with increase in compression ratio the delay period

Decreasing the cooling water temperature in SI engines the knocking tendency

The precess of breaking up or a liquid into fine droplets by spraying is called

Excess quantities of sulphur in diesel fuel are Objectionable because it may cause the following

with increase in compression ratio flame speed

Open combustion chambers in CI engines require

In a cycle, the spark lasts roughly for

It the temperature of intake air in IC engines is lowered, then its efficiency will

Which of the following statements is correct?

Desirable characteristics of the combustion chamber for SI engines to avoid knock is

Increasing the compression ratio in SI engines the knocking tendency

In CI engines the delay period is affected by

Detonation in SI engines occur due to

A high flame speed is obtained in diesel engine when air fuel ratio is

In CI engines knocking tendency increases with

Crankcase explosion in I.C. engines usually occurs as

In diesel engine the diesel fuel injected intc cylinder would burn instantly at about compressed air temperature of

Internal Combustion Engines and Their Advantages and Disadvantages

Diesel Engines and Thermodynamic Cycles

Combustion and Efficiency in Engines

Fuel and Hydrocarbon

Automobile Engine Fuel Systems

Fuel Injection and Ignition Systems in Automotive Engineering

Supercharging and Ignition Timing in Engines

Automotive Engine Lubrication and Cooling System

Engine Cooling, Efficiency, and Emissions

Exhaust Emissions and Control Systems in Vehicles

Filters