1. Octane number of petrol generally available is in the range
Correct : E. 80 to 100
2. In spark ignition engines, the knocking tendency is reduced by
Correct : D. Adding dope like tetra ethy lead to the fuel
3. In thermodynamic analysis, a pure substance is that which
Correct : B. May have a number of chemical species that the composition remains constant
4. Leaking radiator tubes are generally
Correct : A. Soldered
5. When steam expands without doing mechanical work, its enthalpy
Correct : C. Does not change
6. Generally steam turbines in power station operate at
Correct : B. 3000 RPM
7. Thermionic converters are based on
Correct : D. Transfer of electrons
8. Anthydrous substance is
Correct : E. Free of water specially water of crystallization
9. Fuel which detonates easily is
Correct : D. n-Heptane
10. In compression ignition engine fuel ignition accelerators are added to
Correct : A. Reduce combustion knock
11. Working pressure of a boiler does not depend upon
Correct : E. Type of fuel being fired
12. Oil rings are slotted to
Correct : E. Provide an escape for the oil that the slot edges cut from the cylinder wall
13. A gas turbine cycle operates through pressures ratio of 5. Air enters the compressor at atmospheric pressure and 25?C and entry to the turbine is at 800?C. The thermal efficiency of the plant has been found to be 37%. Now, if compressor and turbine efficiencies of 80% are taken into account, the value, of thermal efficiency will be
Correct : D. 17.75%
14. The chemical usually added for increasing the knock resistance of a petrol engine is
Correct : A. Tetra-ethy lead
15. Pure cetane
Correct : C. Is a straight chain paraffin
16. In aircraft using gas turbine the cycle used is
Correct : D. Simple
17. Which of the following automobile is relatively free from pollution problems
Correct : C. Batterly powered
18. During idling a petrol engine requires
Correct : A. Rich mixture
19. A diesel engine is to be redesigned to improve the overload capacity. The design feature which will be influenced is
Correct : E. All of the above
20. Which of the following pollutants result from automobile exhaust?
Correct : E. All of the above
21. Which is incorrect?
Correct : E. None of the above
22. Coking is
Correct : B. Heating of coal in absence of air driving carbon and leaving behind the residue of carbon
23. In a diesel engine the inlet pressure is more than the atmospheric pressure. Therefore; it can be concluded that
Correct : E. The engine is supercharged
24. In a impulse turbine while steam flows through the moving blades
Correct : B. Velocity reduces
25. A hydrograph is a plot of discharge through a river versus
Correct : A. Time
26. 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
Correct : C. 1.04 kg/sq-cm
27. A cross-head has
Correct : A. Reciprocating motion
28. An average percentage of Carbon and Hydrogen in Petrol may be roughly given as
Correct : D. 85% C, 150% H2
29. The overload capacity of diesel engine is usually around
Correct : E. 10%
30. A gas turbine plant operates between 1 ata and 9 ata with minimum and maximum cycle temperature of 25?C and 1000?C. A two stage compressor is provided with perfect intercooling and work is equally divided between the two stages. The intermediate pressure will be
Correct : B. 3 ata
31. In cse the exhaust silencer of a petrol engine is partly choked, it is likely to result in
Correct : B. Increased fuel consumption
32. Which of the following engine uses two fuel simultaneously?
Correct : B. Duel fuel engine
33. Which of the following constituent of air has the least proportion?
Correct : B. Xenon
34. Which of the following is a false statement. A multicylinder diesel engine is missing on one or more cylinders. The cause may be
Correct : D. Air cleaner plugged
35. If a steam injector lifts the water but fails to force it into the boiler, the trouble may not be due to
Correct : C. Sry steam
36. Which one of the following symptoms will not show that combustion is becessary complete.
Correct : D. Presence of nitrogen in exhaust
37. Presence of impurities in ice
Correct : B. Lowers melting point
38. Piston rod is provided in
Correct : B. Double acting steam engines
39. The pressure of steam generated in a boiler as recorded by the Bourdon pressure gauge was 2.2 kg/sq-cm. If the barometer reads 774 mm of mercury the absolute pressure of steam would be
Correct : E. 3.2526 kg/sq-cm
40. Which statement is false in case of SI engines
Correct : A. Accetylene has least tendency to knocking
41. In a petrol engine as the speed increases
Correct : D. The spark has to be retarded
42. In thermodynamics, forced processes are those
Correct : D. Which require an agency outside the system to force the process
43. The steam in a boiler drum is always
Correct : D. Wet
44. Which of the following is false statement? The cause of slow cranking of a gas engine during starting may be
Correct : C. High air temperature
45. The work done on a compressor will be least when air is taken from
Correct : B. Source of low temperature air
46. A coal contains 3.5% sulphur by weight, as fired, and all the sulphur may be assumed to go to formation of sulphur dioxide. How many tonnes of SO2 are produced per day of the firing rate is 35 tonnes per hour
Correct : D. 58.8
47. The total length of 40 mid-ordinates on a simple steam engine indicator diagram is 17 cm. The pressure scale is 0.6 kg/sq-cm. The mean effective pressure would be
Correct : C. 1.0 kg/sq-cm
48. Free air is air at
Correct : E. Atmospheric conditions at any specific location
49. De-Laval turbine is mostly used
Correct : A. For small powers at high speeds
50. Air fuel ratio for a jet engine is of the order of
Correct : C. 60 ; 1
51. A petrol engine as compared to diesel engine (both running at full load) is
Correct : B. Less efficient
52. Which one of the following assumptions is not involved while deriving relation for air standard efficiency of Otto cycle?
Correct : A. The engine operates at mederate rpm
53. Which of the following needs constant cleaning in a diesel engine?
Correct : C. Air, fuel and lubricating oil
54. Bagasse is
Correct : A. Fibrous portion of sugarcane left after extracting the juice
55. During regenerative feed heating
Correct : C. Part of the steam is bled from turbine for feed water heating
56. A jet engine has
Correct : C. No propeller
57. Anti-knock for compression ignition engines is
Correct : C. Hexadecane
58. Which statement is incorrect?
Correct : D. Morse test can be conducted on CFR engine.
59. Advantage of a diesel engine over petrol engine is
Correct : A. Low fuel consumption at full load as well as part load
60. Forced circulation of water does not take place in which of the following boiler?
Correct : D. Lancashire boiler
61. In multistage compression, perfect intercooling means
Correct : A. Temperature of air at inlet to subsequent stages is equal to initial temperature
62. The battery used in vespa scooter is
Correct : A. No battery is used in the scooters
63. Which variety of coal has low calorific value?
Correct : C. Lignite
64. Stoichiometric ratio is
Correct : B. Chemically correct air-fuel ratio by weight
65. Hot spots are
Correct : D. The spots where heavier fractions of fuel are vaporised
66. Air required for complete combustion of 1 kg of carbon is 11.6 kg. If a fuel contains 88.6% Carbon and 11.4% Hydrogen, the air requirement will
Correct : D. Remain unaltered
67. Volumetric efficiency of a well designed engine may be in the range
Correct : C. 75 to 90 percent
68. If the boiler chimney emission consists of dense white smoke, then it can be concluded that
Correct : B. Insufficient air has been supplied for combustion
69. Compression ratio in case of gas engines waries in the range
Correct : B. 5 to 10
70. A back pressure generally operates on pressures in the range
Correct : B. 15 - 40 kg/cm2
71. In automobiles as the speed of vehicle increases the back pressure
Correct : D. Depends on other factors
72. A mechanical indicator is used to determine
Correct : B. Indicated horse power
73. During adiabatic compression
Correct : A. No heat leaves or enters the system
74. Safety valve generally used on high pressure boiler is
Correct : D. Spring type
75. Which of the following engine indicator has least inertia effects?
Correct : C. CRO engine indicator
76. Calorific value of methane gas can be determined by
Correct : D. None of the above
77. Which one of the following factors will not assist in improving thermal efficiency of a compression ignition engine?
Correct : D. High surface to volume ratio
78. A diesel power plant is best suited as
Correct : B. Stand by plant
79. Excessive moisture in steam in a steam turbine is likely to result in
Correct : A. Erosion of turbine blades
80. According to Boyle's law
Correct : D. At constant temperature, the absolute pressure of a gas varies inversely as its volume
81. An optical pyrometer works on the principle of
Correct : B. Mono-chromatic radiation
82. Air fuel ratio for a jet engine is of the order of
Correct : D. 60 ; 1
83. The top ring nearest to the piston crown is known as
Correct : C. Compression ring
84. The vapour pressure is related to the enthalpy of vaporization in
Correct : D. Clausius Clapeyron equation
85. Flash point of a liquids is the temperature at which
Correct : C. The fuel emits vapours at a rate which produces an inflammable mixture with air
86. According to kinetic theory of heat
Correct : A. At absolute zero there is absolutely no vibration of molecules
87. Regenerative feed heating of steam turbines is done primarily to
Correct : C. Improve overall efficiency of the plant
88. Ricardo's theory is associated with
Correct : C. Internal combustion engines
89. A 'blue' flame is
Correct : A. Non-radiant flame
90. The thermal efficiency of a dual cycle engine with fixed compression ratio and fixed quantity of het and with increase in pressure ratio, will
Correct : A. Increase
91. Turbidity in boiler feed water causes
Correct : A. Sludge
92. A mixture containing 60% cetane and 40% Iso-octane will have
Correct : E. None of the above
93. A vacuum of 712 mm was obtained with the barometer reading 753 mm of mercury. The corrected vacuum to a standard barometer of 760 would be
Correct : A. 719 mm Hg
94. Flash point for diesel fuel oil should be
Correct : A. Minimum 49?C
95. The knocking tendency in a compression ignition engine for a given fuel will
Correct : A. Enhance by reducing compression ratio
96. A steam turbine in which a part of the steam turbine after partial expansion is used for process heating and the remaining steam is further expanded for power generation, is known as
Correct : D. Pass out turbine
97. A De-Laval turbine is
Correct : B. Single rotor impulse turbine
98. In a cut off covered steam engine
Correct : A. Admission pressore remains constant while cut off is varied
99. Which one of the following is a safety device on a compressor?