Oil rings are slotted to
A.Provide an escape for the oil that the slot edges cut from the cylinder wall
B.Reduce the bulk
C.Minimise friction
D.Better lubrication of cylinder walls
E.Remove oil from cylinder
Category: Heat Engines Mcqs
For superheated steam in a nozzle the critical pressure ratio is
A.1
B.0.528
C.0.546
D.0.577
E.0.64
Which one of the following factors will not assist in improving thermal efficiency of a compression ignition engine?
A.Fine atomisation and even distribution of fuel
B.Minimum heat loss during combustion
C.Clear exhaust
D.High surface to volume ratio
E.Any of the above
Hot spots are
A.Defects in S.I.engines
B.The hottest spots in engines
C.The spots where heavier fractions of fuel are vaporised
D.Do not exist in engines
E.Hottest point within engine cylinder
A gas used in gas engine trial was tested in a Boys Calorimeter. The pressure of gas supply was 7 cm of water column. If the barometric pressure is 760 mm of mercury, the absolute pressure of the gas would be
A.0.007 kg/sq-cm
B.0.14 kg/sq-cm
C.1.04 kg/sq-cm
D.1.14 kg/sq-cm
E.None of the above
Tenacity is the property of materials in which they
A.Resist indentation
B.Resist rupture
C.Resist shearing
D.Resist deformation
E.None of the above
Calorific value of methane gas can be determined by
A.Bomb calorimeter
B.Bunsen’s apparatus
C.Orsat’s apparatus
D.None of the above
Ignition quality of diesel fuel is expressed by
A.Octane number
B.Cetane number
C.Carbon percentage
D.Calorific value
E.None of the above
A certain gas occupies 2 cu-m at a temperature of 400?C. It receives heat at constant pressure till its temperature is doubled. The change in volume would be
A.3.8 cu-m
B.3.188 cu-m
C.0.038 cu-m
D.0.19 cu-m
E.0.019 cu-m
As the compression ratio increases the volumetric efficiency of air compressor
A.Increases
B.Decreases
C.Does not change
D.Unpredictable
E.None of the above
