Quiznetik

Heat Engines | Set 2

1. The maximum horse power of Fiat engine is around

Correct : C. 40 to 50

2. An air fuel ratio 8 will have

Correct : B. Excess fuel

3. Consumption of diesel in a diesel engine per BHP per hour is in the range

Correct : A. 185-210 gm

4. When a receiver is provided in a compound engine, it can be concluded that

Correct : C. The cranks are at 90? to each other

5. The emission of oxides of nitrogen in automobile exhaust will be least when the vehicle is

Correct : D. Idling

6. A gas turbine works on

Correct : A. Brayton cycle

7. Isolate the factor on which bursting pressure of boiler does not depend

Correct : D. Shear strength of shell material

8. Total solid impurities in feed water for a boiler depend upon

Correct : A. Boiler pressure

9. A cold short metal is

Correct : B. One that cannot be welded

10. The thermal efficiency of steam turbine can be increased by

Correct : D. All of the above

11. If the pressures at the beginning and end of compression in an Otto cycle engine are 1 kg/cm2 and 8 kg/cm2 respectively the air standard efficiency will be

Correct : D. 50%

12. In a reaction turbine which steam flows through the moving blades

Correct : B. Both velocity as well as pressure decreases

13. Which of the following functions reduces the irreversibility of a cycle?

Correct : C. regeneration

14. The intercept of Willian's line on Y-axis at the origin, gives

Correct : D. Idling speed

15. In a throttle governed single cylinder steam engine 5 I.H.P. is developed when steam consumption is 50 kg per hour and 2 I.H.P. is developed when the steam consumption is 26 kg per hour. The steam consumptions when the engine develops 4 I.H.P. will be

Correct : B. 42 kg

16. The efficiency of a jet propulsion unit is generally high at altitudes of

Correct : E. More than 10,000 metres

17. Which of the following is not used as ignition accelerator for diesel engine fuel?

Correct : B. Methyl alcohol

18. The ideal output velocity of steam from a nozzle having an enthalpy drop of 100 kcal/kg will be

Correct : D. 915 m/s

19. In a four stroke engine if a valve opens 25? before B.D.C. and closes 10? after T.D.C. the valve should be

Correct : E. Exhaust valve

20. If the air clearance is removed in a carburettor engine the fuel air ratio will be

Correct : B. Lower

21. A fan is being used under certain known conditions. If the speed of fan is doubled the air displaced by the fan

Correct : B. Will be doubled

22. The maximum temperature in a gas turbine is of the order of

Correct : A. 700?C

23. Which of the following is a part of reciprocating steam engine and not a part of steam turbine plant?

Correct : D. Cross head

24. For same output and same compression ratio four stroke SI engines as compared to two stroke engines have

Correct : C. Higher thermal efficiency

25. For the same temperature limits and heat input, the most efficient cycle is

Correct : A. Carnot

26. The power for the propulsion of ship is provided by

Correct : C. Either (A) and (B) above

27. The steam trap is used to

Correct : B. Separate condensate from steam

28. Piston ring are plated with chromium, cadmium or phosphate to

Correct : A. Reduce wear and eliminate scuffing

29. More test is conducted on

Correct : B. Multi-cylinder engines

30. In oil burners air is supplied

Correct : C. To improve combustion efficiency

31. In a compression ignition engine higher combustion chamber wall temperature will

Correct : A. Reduce knocking tendency

32. Clapeyron equation is applicable

Correct : D. For change of state when two phases are in equilibrium

33. In a system if base load is same as maximum demand, the load factor will be

Correct : A. 1

34. Reheating of steam for steam turbine cycle is done primarily to

Correct : D. Improve thermal efficiency of the plant

35. Morse test is conducted on

Correct : A. Multi-cylinder engines

36. Capacitor kVA required to bring the power factor of a 500 kW load 70% to 85% would be

Correct : E. 200 kVA

37. The function of a condenser in a steam power plant is

Correct : E. To reduce back pressure

38. For diatomic gas flowing through a nozzle the critical pressure ratio is given by

Correct : C. 3.546

39. Suri-transmission is

Correct : A. hydro-mechanical

40. The temperature of the blades of a gas turbine may be closer to

Correct : C. 1200?C

41. Compression ratio for diesel engines is generally in the range

Correct : D. 14 to 22

42. In case of pressure compounded impulse turbine, for the steam while flowing through the nozzle of second stage

Correct : A. Pressure drops while velocity increases

43. Which spark plug will have lower heat rating

Correct : C. W 95 T1

44. In a petrol engine fuel lock generally occurs in

Correct : D. Pump

45. As per IS specifications the endurance test for engines is conducted for

Correct : A. 500 hours

46. In a pumping installation the suction line is is 4 metre long and suction pipe diameter is 100 mm. Now if the suction pipe is replaced by a pipe combination consisting of 2 metres of 100 mm diameter pipe joined with 2 metres of 150 mm diameter pipe, the suction heat will become

Correct : B. 4 metres

47. Standard air is air at

Correct : A. Atmospheric conditions at any specific location

48. Which of the following is not needed in case of magneto ignition?

Correct : D. Battery

49. During detonation in a petrol engine

Correct : D. The rate of pressure rise is high

50. Volume of air at 27?C is 2 cu-m. What will be the volume at 327?C

Correct : C. 4 cu-m

51. The air standard efficiency of a Diesel engine depends on

Correct : E. Compression ratio

52. The size of a steam engine is 200 x 250 - 300 r.p.m. In this 200 indicates

Correct : E. Cylinder bore

53. In multistages turbines by introducting reheating

Correct : A. Thermal efficiency improves

54. In order to reduce wear and eliminate scuffing, piston ring in internal combustion engines are

Correct : E. Plated with chromium, cadmium or phosphate

55. The ends of piston rod in steam engines are connected to

Correct : D. Piston and cross-head

56. One horse power-hr is equal to

Correct : B. 632 kcal

57. Which of the following boiler uses exhaust of the engine to produce draught?

Correct : E. Locomotive boiler

58. In jet engine the compression ratio

Correct : C. Varies as square of speed

59. Pour point is the temperature at which oil

Correct : C. Barely flows

60. Which one of the following factors will not assist in smooth running of a compression ignition engine?

Correct : D. High ignition temperature of fuel

61. In case of an opposed piston engine the combustion chamber

Correct : B. Is formed between two piston tops

62. Specific heat is

Correct : C. The ratio of quantity of heat required to raise the temperature of a given weight of any substance through 1?C to the quantity of heat required to raise the temperature of same weight of water through 1?C

63. In a diesel engine the injection pressure is of the order of

Correct : B. 100 kg/cm2

64. If a water cooled compressor knocks during operation, the probable cause cannot be

Correct : D. Excess cooling in intercooler

65. Thermal efficiency of a compression ignition engine may be of the order of

Correct : A. 35%

66. In centrifugal pumps suction head is

Correct : C. (A) Above less velocity heat

67. Maintenance requirements are least in case of

Correct : A. Electric locomotives

68. The higher the temperature required to ignite diesel fuel,

Correct : C. Lower the cetane number

69. In pumped storage systems, water is pumped

Correct : B. Upstream during off peak periods

70. The supercharging of diesel engine is done mainly to

Correct : C. Increase the power output

71. In Eicher tractor the engine is

Correct : A. Air cooled

72. Air fuel ratio in a petrol engine fitted with dirty air cleaner as compared to that with clean air clearance will be

Correct : C. Lower

73. Crankshafts are generally

Correct : D. Forged

74. In a condensing steam engine

Correct : A. Exhaust steam is condensed in condenser

75. The Apparatus used for the determination of calorific value of solid fuel is

Correct : C. Bomb calorimeter

76. Stuffing box is provided in

Correct : E. Double acting steam engines

77. An exciter is a

Correct : B. D.C.generator

78. An engine operates at 1440 rpm under load whereas no load speed is 1500 rpm. The percentage speed drop of governor will be

Correct : C. 4%

79. In a Bomb calorimeter the fuel to be tested is burnt

Correct : A. At constant volume

80. Which fuel will have least air consumption during combustion

Correct : A. Spirit

81. Movement of air inside engine cylinder does not help in

Correct : D. Reducing noise

82. In a Lancashire boiler, the economiser is located

Correct : A. Before air preheater

83. Iso-octane has octane number of

Correct : A. 100

84. Freezing point of petrol is around

Correct : B. ?30?C

85. 1 Torr is equivalent to

Correct : A. 1 mm Hg

86. The most effective air cleaner for diesel engines is

Correct : B. Oil bath type

87. An economiser is installed in a boiler plant primarily to

Correct : E. Reduce fuel consumption

88. The equilibrium conditions between supersaurated vapour and a cooled liquid surface are expressed in

Correct : C. Kelvin Helmhotz equation

89. Most of the heat generated in I.C. engines is transferred to surrounding medium by

Correct : C. Conduction and convection

90. Vapour lock is

Correct : C. Complete or partial stoppage of fuel supply due to vaporisation of fuel in supply steam

91. The steam pressure in a pass out turbine may be expected to be in the range

Correct : A. 10 kg/cm2 to 20 kg/cm2

92. A regenerator in a gas turbine

Correct : C. Improves thermal efficiency

93. Higher proportion of residual gases in the cylinder would mean

Correct : B. Lower volumetric efficiency

94. Low grade fuels have

Correct : C. Low calorific valve

95. A gas turbine cycle with regenerator has a thermal efficiency of 26%. If intercooler and reheater are also introduced what could be expected thermal efficiency

Correct : E. 30%

96. Free piston engines find application in

Correct : C. Gas turbines

97. In case of supersonic flow through the nozzle, when the cross-section increases in the direction of flow

Correct : C. The velocity will increase while the pressure will decrease in the direction of flow

98. The performance of air compressor at high altitudes as compared to that at sea level will be

Correct : E. Inferior

99. To avoid moisture trubles, the branch connection from compressed air line are taken from

Correct : A. Top side

100. Which turbine has identical fixed and moving blades

Correct : C. Parson's reaction turbine