The specific fuel consumption per B.P. hour for a petrol engine is about
0.2 kg
0.25 kg
0.3 kg
0.35 kg
Correct Answer :
B. 0.25 kg
Related Questions
Pour point of fuel oil is the
Minimum temperature to which oil is heated in order to give off inflammable vapours in sufficient quantity to ignite momentarily when brought in contact with a flame
Temperature at which it solidifies or congeals
It catches fire without external aid
Indicated by 90% distillation temperature i.e., when 90% of sample oil has distilled off
In a petrol engine, the fuel supplied to the engine cylinder is mixed with required quantity of air and the mixture is ignited with a
Fuel pump
Fuel injector
Spark plug
None of these
During idling, a petrol engine requires _________ mixture.
Lean
Rich
Chemically correct
None of these
Theoretically, a four stroke cycle engine should develop _________ power as that of a two stroke cycle engine.
Half
Same
Double
Four times
In petrol engines, advancing of the spark timing will _________ the knocking tendency.
Not effect
Decrease
Increase
None of these
A petrol engine, during suction stroke draws
Air only
Petrol only
A mixture of petrol and air
None of these
A two stroke cycle engine gives ________ the number of power strokes as compared to the four stroke cycle engine, at the same engine speed.
Half
Same
Double
Four times
Air fuel ratio at which a petrol engine cannot work is
8 : 1
10 : 1
15 : 1
20 : 1 and less
If V₁ is the jet velocity and V₀ is the vehicle velocity, then propulsive efficiency of a turbojet engine is
V₁/(V₀ + V₁)
V₀/(V₀ + V₁)
2V₀/(V₀ + V₁)
2V₁/(V₀ + V₁)
The maximum propulsive efficiency of a turbojet engine is at a speed of
1000 km/h
2000 km/h
2400 km/h
3000 km/h
The actual volume of fresh charge admitted in 4-stroke petrol engine is
Equal to stroke volume
Equal to stroke volume and clearance volume
Less than stroke volume
More than stroke volume
In a four stroke cycle diesel engine, the exhaust valve
Opens at 30° before bottom dead centre and closes at 10° after top dead centre
Opens at 30° after bottom dead centre and closes at 10° before top dead centre
Opens at bottom dead centre and closes at top dead centre
May open and close anywhere
The pressure and temperature at the end of compression stroke in a petrol engine are of the order of
4-6 kg/cm² and 200-250°C
6-12 kg/cm² and 250-350°C
12-20 kg/cm² and 350-450°C
20-30 kg/cm² and 450-500°C
In case of gas turbines, the gaseous fuel consumption guarantees are based on
High heat value
Low heat value
Net calorific value
Calorific value
The power actually developed by the engine cylinder of an I.C. engine is known as
Theoretical power
Actual power
Indicated power
None of these
If the speed of the engine is increased, the indicated power will
Increase
Decrease
Remain same
None of these
The reflectivity depends upon
Geometry of the reflector
Energy of neutrons
Properties of the reflector
All of these
The frictional power (F.P.) is given by
F.P. = B.P. - I.P.
F.P. = I.P. - B.P.
F.P. = B.P./I.P.
F.P. = I.P./B.P.
The theoretically correct air fuel ratio for petrol engine is of the order of
6 : 1
9 : 1
12 : 1
15 : 1
In a typical medium speed 4-stroke cycle diesel engine the inlet valve
Opens at 20° before top dead center and closes at 35° after the bottom dead center
Opens at top dead center and closes at bottom dead center
Opens at 10° after top dead center and closes 20° before the bottom dead center
May open or close anywhere
The compression ignition engines are governed by
Hit and miss governing
Qualitative governing
Quantitative governing
Combination of (B) and (C)
Which of the following statement is wrong?
In compression ignition engines, detonation occurs near the beginning of combustion.
Since the fuel, in compression ignition engines, is injected at the end of compression stroke, therefore, there will be no pre-ignition.
To eliminate knock in compression ignition engines, we want to achieve auto-ignition not early and desire a long delay period.
In compression ignition engines, because of heterogeneous mixture, the rate of pressure rise is comparatively lower.
Which of the following is false statement? Some of the methods used to reduce diesel smoke are as follows
Using additives in the fuel
Increasing the compression ratio
Adherence to proper fuel specification
Avoidance of overloading
Pick up the wrong statement about supercharging
Supercharging reduces knocking in diesel engines
There can be limited supercharging in petrol engines because of detonation
Supercharging at high altitudes is essential
Supercharging results in fuel economy
The accumulation of carbon in a cylinder results in increase of
Clearance volume
Volumetric efficiency
Ignition time
Effective compression ratio
The specific fuel consumption per B.P. hour for a petrol engine is about
0.2 kg
0.25 kg
0.3 kg
0.35 kg
Diesel fuel, compared to petrol is
Less difficult to ignite
Just about the same difficult to ignite
More difficult to ignite
Highly ignitable
In a four stroke cycle petrol engine, the expansion
Starts at top dead centre and ends at bottom dead centre
Starts at 30° before top dead centre and ends at 50° before bottom dead centre
Starts at 30° after top dead centre and ends at 50° after bottom dead centre
May start and end anywhere
The air standard efficiency of an Otto cycle compared to diesel cycle for the given compression ratio is
Same
Less
More
More or less depending on power rating
The air requirement of a petrol engine during starting compared to theoretical air required for complete combustion is
More
Less
Same
May be more or less depending on engine capacity