Home
Current Affairs January 2024

What is the correct answer?

4

The air requirement of a petrol engine during starting compared to theoretical air required for complete combustion is

A. More

B. Less

C. Same

D. May be more or less depending on engine capacity

Correct Answer :

B. Less


Related Questions

What is the correct answer?

4

Iso-octane (C8H18) has octane number of

A. 0

B. 50

C. 100

D. 120

What is the correct answer?

4

The inlet value of a four stroke cycle I.C engine remains open for nearly

A. 180°

B. 125°

C. 235°

D. 200°

What is the correct answer?

4

The fuels in order of decreasing knock tendency for spark ignition engines are

A. Paraffin, aromatic, napthene

B. Paraffin, napthene, aromatic

C. Napthene, aromatics, paraffin

D. Napthene, paraffin, aromatic

What is the correct answer?

4

A heat engine utilises the

A. Calorific value of oil

B. Low heat value of

C. High heat value of oil

D. Mean heat value of oil

What is the correct answer?

4

In a four stroke cycle, the minimum temperature inside the engine cylinder occurs at the

A. Beginning of suction stroke

B. End of suction stroke

C. Beginning of exhaust stroke

D. End of exhaust stroke

What is the correct answer?

4

The ignition of the charge by some hot surface within the engine before the passage of spark is called

A. Pre-ignition

B. Detonation

C. Ignition delay

D. Auto-ignition

What is the correct answer?

4

The reason for supercharging in any engine is to

A. Increase efficiency

B. Increase power

C. Reduce weight and bulk for a given output

D. Effect fuel economy

What is the correct answer?

4

Does the supply of scavenging air at a density greater than that of atmosphere mean engine is supercharged?

A. Yes

B. No

C. To some extent

D. Unpredictable

What is the correct answer?

4

Which of the following is false statement? Some of the methods used to reduce diesel smoke are as follows

A. Using additives in the fuel

B. Increasing the compression ratio

C. Adherence to proper fuel specification

D. Avoidance of overloading

What is the correct answer?

4

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

What is the correct answer?

4

If V₁ is the jet velocity and V₀ is the vehicle velocity, then propulsive efficiency of a turbojet engine is

A. V₁/(V₀ + V₁)

B. V₀/(V₀ + V₁)

C. 2V₀/(V₀ + V₁)

D. 2V₁/(V₀ + V₁)

What is the correct answer?

4

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

A. Not effected

B. Decrease

C. Increase

D. None of these

What is the correct answer?

4

A diesel engine, during suction stroke, draws

A. Air only

B. Diesel only

C. A mixture of diesel and air

D. None of these

What is the correct answer?

4

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

A. Equal to

B. Less than

C. Greater than

D. None of these

What is the correct answer?

4

In petrol engines, advancing of the spark timing will _________ the knocking tendency.

A. Not effect

B. Decrease

C. Increase

D. None of these

What is the correct answer?

4

A 75 cc engine has following parameter as 75 cc

A. Fuel tank capacity

B. Lube oil capacity

C. Swept volume

D. Cylinder volume

What is the correct answer?

4

The delay period in compression ignition engines depends upon

A. Temperature and pressure in the cylinder at the time of injection

B. Nature of the fuel mixture strength

C. Relative velocity between the fuel injection and air turbulence pressure of residual gases

D. All of the above

What is the correct answer?

4

The magneto in an automobile is basically

A. Transformer

B. D.C. generator

C. Capacitor

D. Magnetic circuit

What is the correct answer?

4

The pressure at the end of compression, in diesel engines, is approximately

A. 10 bar

B. 20 bar

C. 25 bar

D. 35 bar

What is the correct answer?

4

The theoretically correct mixture of air and petrol is

A. 10 : 1

B. 15 : 1

C. 20 : 1

D. 25 : 1

What is the correct answer?

4

The temperature of interior surface of cylinder wall in normal operation is not allowed to exceed

A. 80°C

B. 120°C

C. 180°C

D. 240°C

What is the correct answer?

4

The probability of knocking in diesel engines is increased by

A. High self ignition temperature

B. Low volatility

C. Higher viscosity

D. All of these

What is the correct answer?

4

A diesel engine as compared to petrol engine (both running and rated load) is

A. More efficient

B. Less efficient

C. Equally efficient

D. Other factors will decide it

What is the correct answer?

4

The injection pressure in a diesel engine is about

A. 10 bar

B. 100 bar

C. 150 bar

D. 500 bar

What is the correct answer?

4

The mechanical efficiency (ηm) of the engine is given by

A. ηm = B.P/I.P

B. ηm = I.P/B.P

C. ηm = (B.P × I.P)/100

D. None of these

What is the correct answer?

4

In a four stroke cycle diesel engine, the compression

A. Starts at 40° after bottom dead centre and ends at 10° before top dead centre

B. Starts at 40° before top dead centre and ends at 40° after top dead centre

C. Starts at top dead centre and ends at 40° before bottom dead centre

D. May start and end anywhere

What is the correct answer?

4

The ignition quality of diesel oil is expressed by

A. Cetane number

B. Octane number

C. Calorific value

D. None of these

What is the correct answer?

4

In loop scavenging, the top of the piston is

A. Flat

B. Contoured

C. Slanted

D. Depressed

What is the correct answer?

4

The pressure and temperature at the end of compression stroke in a petrol engine are of the order of

A. 4-6 kg/cm² and 200-250°C

B. 6-12 kg/cm² and 250-350°C

C. 12-20 kg/cm² and 350-450°C

D. 20-30 kg/cm² and 450-500°C

What is the correct answer?

4

A supercharged engine as compared to an ordinary engine

A. Is lighter

B. Requires smaller foundations

C. Consumes less lubricating oil

D. All of these