The method of determination of indicated power of a multi cylinder spark ignition engine is by the use of
Morse test
Prony brake test
Motoring test
Heat balance test
Correct Answer :
A. Morse test
Related Questions
Alpha-methyl-naphthalene (C₁₁ H₁₀) has a cetane number of
0
50
100
120
The air-fuel ratio of the petrol engine is controlled by
Carburettor
Injector
Governor
None of these
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
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
The _________ engines can work on very lean mixture of fuel.
Spark ignition
Compression ignition
Both (A) and (B)
None of these
The volumetric efficiency of a well designed engine may be
30 to 40 %
40 to 60 %
60 to 70 %
75 to 90 %
The process of breaking up or a liquid into fine droplets by spraying is called
Vaporisation
Carburetion
Ionisation
Atomisation
The exhaust valve in a four stroke cycle petrol engine
Opens at 50° before bottom dead centre and closes at 15° after top dead centre
Opens at bottom dead centre and closes at top dead centre
Opens at 50° after bottom dead centre and closes at 15° before top dead centre
May open and close anywhere
A diesel engine has
One valve
Two valves
Three valves
Four valves
Engine pistons are usually made of aluminium alloy because it
Is lighter
Wear is less
Absorbs shocks
Is stronger
Compression loss in I.C engines occurs due to
Leaking piston rings
Use of thick head gasket
Clogged air inlet slots
All of the above
Which of the following does not relate to a spark ignition engine?
Ignition coil
Spark plug
Carburettor
Fuel injector
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
Number of working strokes per min. for a four stroke cycle engine are _________ the speed of the engine in r.p.m.
Equal to
One-half
Twice
Four-times
The ignition quality of petrol is expressed by
Cetane number
Octane number
Calorific value
All of these
A mixture containing 65% of iso-octane and 35% of normal heptane will have
Cetane number 65
Octane number 65
Cetane number 35
Octane number 35
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 knocking in spark ignition engines can be reduced by
Retarding the spark
Increasing the engine speed
Both (A) and (B)
None of these
The pressure at the end of compression in the case of diesel engine is of the order of
6 kg/cm
12 kg/cm
20 kg/cm
35 kg/cm
The two reference fuels used for cetane rating are
Cetane and iso-octane
Cetane and alpha-methyl naphthalene
Cetane and normal heptane
Cetane and tetra ethyl lead
In loop scavenging, the top of the piston is
Flat
Contoured
Slanted
Depressed
Scavenging air in diesel engine means
Air used for combustion sent under pressure
Forced air for cooling cylinder
Burnt air containing products of combustion
Air used for forcing burnt gases out of engine's cylinder during the exhaust period
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
The thermal efficiency of a diesel cycle having fixed compression ratio, with increase in cut-off ratio will
Increase
Decrease
Be independent
May increase or decrease depending on other factors
Which one of the following event would reduce volumetric efficiency of a vertical compression ignition engine?
Inlet valve closing after bottom dead centre
Inlet valve closing before bottom dead centre
Inlet valve opening before top dead centre
Exhaust valve closing after top dead centre
A spark plug gap is kept from
0.3 to 0.7 mm
0.2 to 0.8 mm
0.4 to 0.9 mm
0.6 to 1.0 mm
Which of the following is false statement? Excess quantities of sulphur in diesel fuel are Objectionable because it may cause the following
Piston ring and cylinder wear
Formation of hard coating on piston skirts
Oil sludge in the engine crank case
Detonation
The output of a diesel engine can be increased without increasing the engine revolution or size in following way
Feeding more fuel
Heating incoming air
Scavenging
Supercharging
The turbine of the turboprop engine is __________ that of the turbojet engine.
Same as
Smaller than
Bigger than
None of these
The probability of knocking in diesel engines is increased by
High self ignition temperature
Low volatility
Higher viscosity
All of these