Q.1

In a petrol engine, the mixture has the lowest pressure at the

  • beginning of suction stroke
  • end of suction stroke
  • end of compression stroke
  • none of these
Q.2

A diesel engine is __________ as compared to petrol engine, both running at rated load.

  • equally efficient
  • less efficient
  • more efficient
Q.3

The indicated power for multi-cylinder engine will be same as that of a single cylinder engine.

  • True
  • False
Q.4

The ratio of the heat equivalent to one kW hour to the heat in fuel per B.P. hour is termed as brake thermal efficiency.

  • Yes
  • No
Q.5

Solid fuel fabricated into various small shapes, which are assembled to form fuel elements, is in the form of

  • plates
  • pallets
  • pins
  • all of these
Q.6

The air standard efficiency of an I.C. engine depends on

  • fuel used
  • speed of engine
  • compression ratio
  • none of these
Q.7

Supercharging __________ the power developed by the engine.

  • has no effect on
  • increases
  • decreases
Q.8

The compression ratio in petrol engines is kept low as compared to diesel engines because higher compression ratio in petrol engines would lead to pre-ignition of fuel.

  • Agree
  • Disagree
Q.9

The scavenging efficiency of a four stroke cycle diesel engine is

  • below 50%
  • between 50 and 85%
  • between 85 and 95%
  • between 95 and 100%
Q.10

The thermal efficiency of diesel engines is about

  • 15%
  • 30%
  • 50%
  • 70%
Q.11

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

  • not effect
  • decrease
  • increase
Q.12

The secondary fuel used in nuclear power plants is

  • U233 and Pu239
  • U235 and Th232
  • U235 and Pu238
  • U233 and Pu238
Q.13

The injection pressure in a diesel engine is about

  • 10 bar
  • 100 bar
  • 150 bar
  • 500 bar
Q.14

The predominent isotope of the naturally occuring element is

  • U235
  • U238
  • Pu233
  • Pu239
Q.15

A carburettor is used to supply

  • petrol, air and lubricating oil
  • air and diesel
  • petrol and lubricating oil
  • petrol and air
Q.16

Spark plugs in automobiles generally have a gap between

  • 0.3 to 0.7 mm
  • 0.2 to 0.8 mm
  • 0.4 to 0.9 mm
  • 0.6 to 1.8 mm
Q.17

A diesel engine has compression ratio from

  • 6 to 10
  • 10 to 15
  • 15 to 25
  • 25 to 40
Q.18

The correct sequence of the decreasing order of brake thermal efficiency of the three given basic types of engines is

  • four stroke C.I. engine, four stroke S.I. engine, two stroke S.I. engine
  • four stroke S.I. engine, four stroke C.I. engine, two stroke S.I. engine
  • four stroke C.I. engine, two stroke S.I. engine, four stroke S.I. engine
  • two stroke S.I. engine, four stroke S.I. engine, four stroke C.I. engine
Q.19

The indicated mean effective pressure of an engine is obtained from the indicator diagram drawn with the help of an engine indicator.

  • True
  • False
Q.20

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 hetrogeneous mixture, the rate of pressure rise is comparatively lower.
Q.21

In a petrol engine, the charge is ignited with the help of a spark plug.

  • Yes
  • No
Q.22

A diesel engine has compression ratio from

  • 6 to 10
  • 10 to 15
  • 15 to 25
  • 25 to 40
Q.23

A nuclear power plant differs from a conventional steam power station only in the steam generating part.

  • Agree
  • Disagree
Q.24

The thermodynamic cycle on which the petrol engine works, is

  • Otto cycle
  • Joule cycle
  • Rankine cycle
  • Stirling cycle
Q.25

The object of supercharging the engine is

  • to reduce mass ofthe engine per brake power
  • to reduce space occupied by the engine
  • to increase the power output of an engine when greater power is required
  • all ofthe above
Q.26

Which of the following does not relate to a spark ignition engine ?

  • Ignition coil
  • Spar kplug
  • Carburettor
  • Fuel injector
Q.27

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
Q.28

In order to prevent knocking in spark ignition engines, the charge away from the spark plug should have

  • low density
  • low temperature
  • long ignition delay
  • all of these
Q.29

The theoretically correct mixture of air and petrol is

  • 10:1
  • 15:1
  • 20:1
  • 25:1
Q.30

Which of the following statement is wrong ?

  • A four stroke cycle engine develops twice the power as that of a two stroke cycle engine.
  • For the same power developed, a four stroke cycle engine is lighter, less bulky and occupies less floor area.
  • The petrol engines are costly than diesel engines.
  • all of the above
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