The firing order in an I.C. engine depends upon
Arrangement of the cylinders
Design of crankshaft
Number of cylinders
All of these
Correct Answer :
D. All of these
Related Questions
A diesel engine as compared to petrol engine (both running and rated load) is
More efficient
Less efficient
Equally efficient
Other factors will decide it
In a four stroke cycle petrol engine, the inlet valve
Opens at top dead centre and closes at bottom dead centre
Opens at 20° before top dead centre and closes at 40° after bottom dead centre
Opens at 20° after top dead centre and closes at 20° before bottom dead centre
May open or close anywhere
The theoretically correct mixture of air and petrol is
10 : 1
15 : 1
20 : 1
25 : 1
Morse test is used to determine the I.P. of a
Single cylinder petrol engine
Four stroke engine
Single cylinder diesel engine
Multi cylinder engine
For the same compression ratio
Otto cycle is more efficient than the Diesel
Diesel cycle is more efficient than Otto
Both Otto and Diesel cycles are, equally efficient
Compression ratio has nothing to do with efficiency
The air-fuel ratio of the petrol engine is controlled by
Carburettor
Injector
Governor
None of these
In a petrol engine, if diesel is used, then the engine will
Not run
Run more efficiently
Run at high speed
Explode
The probability of knocking in diesel engines is increased by
High self ignition temperature
Low volatility
Higher viscosity
All of these
The thermodynamic cycle on which the petrol engine works, is
Otto cycle
Joule cycle
Rankine cycle
Stirling cycle
Number of working strokes per min. for a two stroke cycle engine is _________ the speed of the engine in r.p.m.
Equal to
One-half
Twice
Four-times
The loud pulsating noise heard within the cylinder of an internal combustion engine is known as
Detonation
Turbulence
Pre-ignition
Supercharging
In a four stroke cycle petrol engine, the compression
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
May start and end anywhere
The theoretically correct air fuel ratio for petrol engine is of the order of
6 : 1
9 : 1
12 : 1
15 : 1
The sensing element in the control system of nuclear reactors measures the _________ of the neutron flux in the reactor.
Temperature
Volume
Density
None of these
The calorific value of gaseous fuels is expressed in terms of
kcal
kcal/kg
kcal/m²
kcal/m3
The injection pressure in a diesel engine is about
10 bar
100 bar
150 bar
500 bar
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.
If the compression ratio of an engine working on Otto cycle is increased from 5 to 7, the percentage increase in efficiency will be
2 %
4 %
8 %
14 %
The basic requirement of a good combustion chamber is
Minimum turbulence
Low compression ratio
High thermal efficiency and power output
Low volumetric efficiency
For the same power developed in I.C. engines, the cheaper system is
Naturally aspirated
Supercharged
Centrifugal pump
Turbo charger
The advancing of spark timing in spark ignition engines will _________ knocking tendency.
Increase
Reduce
Not effect
None of these
The mechanical efficiency (ηm) of the engine is given by
ηm = B.P/I.P
ηm = I.P/B.P
ηm = (B.P × I.P)/100
None of these
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
A diesel engine, during suction stroke, draws
Air only
Diesel only
A mixture of diesel and air
None of these
The normal heptane (C7H16) is given a rating of ________ octane number.
0
50
100
120
The brake power of a diesel engine, keeping other parameters constant, can be increased by
Decreasing the density of intake air
Increasing the temperature of intake air
Increasing the pressure of intake air
Decreasing the pressure of intake air
Diesel engine can work on very lean air fuel ratio of the order of 30: 1. A petrol engine can also work on such a lean ratio provided
It is properly designed
Best quality fuel is used
Cannot work as it is impossible
Flywheel size is proper
Antiknock for compression ignition engines is
Napthene
Tetra ethyl lead
Amyl nitrate
Hexadecane
The voltage required to produce a spark across the gap, between the sparking points is
2000 to 4000 volts
4000 to 6000 volts
6000 to 10,000 volts
10,000 to 12,000 volts
The operation of forcing additional air under pressure in the engine cylinder is known as
Scavenging
Turbulence
Supercharging
Pre-ignition