51. Rotary compressor is best suited for_____________________?
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A. small quantity of air at high pressure

B. large quantity of air at high pressure

C. any one of the above

D. large quantity of air at low pressure

E. small quantity of air at low pressure

52. Free air is the air at________________?
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A. 25C, 1 kg/cm2 and relative humidity of 50%.

B. 0C and standard atmospheric conditions

C. 15C and 1 kg/cm2

D. atmospheric conditions at any specific location

E. 20C and 1 kg/cm2 and relative humidity of 36%

53. For hypersonic flow, the Mach number is___________________?
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A. greater than 4

B. greater than unity

C. unity

D. greater than 10

E. greater than 2

54. Ratio of indicated h.p. to shaft h.p. in known as__________________?
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A. isothermal efficiency

B. adiabatic efficiency

C. volumetric efficiency

D. compressor efficiency

E. mechanical efficiency
55. Buoyant force is___________________?
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A. resultant force acting on a floating body

B. the resultant force on a body due to the fluid surrounding it

C. none of the above

D. equal to the volume of liquid displaced

E. force necessary to keep a body in equilibrium

56. An ideal air compressor cycle with clearance on p-v diagram can be represented by following processes_______________?
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A. two adiabatic and two isobaric

B. one adiabatic, one isobaric and two constant volume

C. one adiabatic, two isobaric, and one constant volume

D. two isobaric, two adiabatic and one constant volume

E. two adiabatic, one isobaric and one constant volume,

57. The unit of power in S.I. units is______________?
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A. kilogram meter/sec

B. watt

C. joule

D. newton meter

E. pascal per sec

58. Aeroplanes employ following type of compressor_______________?
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A. none of the above

B. axial flow

C. centrifugal

D. combination of above

E. radial flow

59. Out of the following, from where you will prefer to take intake for air compressor_________________?
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A. from an air conditioned room maintained at 20C

B. from a side where cooling tower is located nearby

C. from coal yard side

D. from outside atmosphere at 1C

E. from any one of the above locations

60. Eulers equation is applicable for__________________?
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A. pumps

B. centrifugal compressor

C. none of the above

D. all of the above

E. axial compressor

61. The overall isothermal eiffciency of compressor is defined as the ratio of_______________?
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A. power to drive compressor to isothermal h.p.

B. work to compress air isothermally to work for actual compression

C. isothermal h.p. to the BHP of motor

D. isothermal h.p. to adiabatic h.p.

E. isothermal work to ideal work

62. Adiabatic compression is one in which___________________?
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A. entropy decreases

B. temperature during compression remains constant

C. temperature rise follows a linear relationship

D. work done is maximum

E. no heat leaves or enters the compressor cylinder during cornpression
63. For supplying intermittent small quantity of air at high pressure, following compressor is best suited__________________?
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A. centrifugal

B. axial

C. screw

D. turbo jet

E. reciprocating
64. To avoid moisture troubles, the branch connections from compressed air lines should be taken from_________________?
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A. left side of main

B. any location

C. right side of main

D. top side of main

E. bottom side of main

65. In a centrifugal pump casing, the flow of water leaving the_______________?
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A. radial

B. vortex

C. rectilinear

D. radial

E. centrifugal

66. In jet engines the products of combustion after passing through the gas lurbine are discharged into_______________?
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A. discharge nozzle

B. atmosphere

C. vacuum

D. back to the compressor

E. none of the above

67. A hydraulic intensifier normally consists of __________________?
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A. two cylinders, two rams and a storage device

B. special type of pump with storage device and a pressure regulator

C. a cylinder, a piston, storage tank and control valve

D. a cylinder and a ram

E. two co-axial rams and two cylinders
68. High specific speed of a pump implies it is_____________________?
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A. any one of the above

B. none of the above

C. axial flow pump

D. centrifugal pump

E. mixed flow pump

69. The following is true for an open cycle gas turbine having exhaust heat exchanger. Atmospheric air before entering the compressor is____________________?
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A. bled gas from turbine is heated and readmitted for complete expansion

B. heated

C. compressed air before entering the combustion chamber is heated

D. part of exhaust gases are heated and mixed up with atmospheric air to utilise exhaust heat

E. exhaust gases drive the compressor

70. Producer gas is produced by_____________________?
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A. partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast

B. same way as the natural gas

C. passing air and a large amount of steam over waste coal at about 65C

D. passing steam over incandescent coke

E. carbonisation of coal

71. Axial flow pump is started with its delivery valve________________?
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A. none of the above

B. kept 50% open

C. irrespective of any position

D. kept fully open

E. kept fully closed

72. A rocket works with maximum overall efficiency when air craft velocity is equal to the_________________?
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A. half the jet velocity

B. jet velocity

C. twice the jet velocity

D. average of the jet velocity

E. no such co-relationship with jet velocity exists

73. Hydraulic accumulator is used for____________________?
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A. generally high pressures to operate hydraulic machines

B. supplying large quantities of oil for very short duration

C. accumulating oil

D. supplying energy when main supply fails

E. accumulating hydraulic energy

74. Which of the following plants is smallest and lightest for genrating a given amount of power__________________?
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A. solar plant

B. steam power plant

C. gas turbine plant

D. diesel engine

E. petrol engine

75. The material commonly used for air craft gas turbine is__________________?
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A. stainless steel

B. high alloy steel

C. duralumin

D. titanium

E. Timken, Haste and Inconel allpys
76. According to fan laws, for fans having constant wheel diameter, the pressure varies________________?
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A. square of fan speed

B. square root of fan speed

C. cube of fan speed

D. none of the above

E. directly as fan speed

77. The ideal efficiency of simple gas turbine cycle depends on________________?
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A. none of the above

B. all of the above

C. minimum cycle temperature

D. pressure ratio

E. maximum cycle temperature

78. The compression ratio in a jet engine varies proportional to ____________________?
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A. speed

B. does not Vary

C. altitude

D. speed

E. Vspeed

79. Intercooling in gas turbine results in ____________________ ?
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A. increase in net output but decrease in thermal efficiency

B. increase in thermal efficiency but decrease in net output

C. increase in both thermal efficiency and net output

D. decrease in both thermal efficiency and net output

E. none of the above

80. Fast breeder reactor uses___________________?
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A. double circuit system of coolant cycle

B. boiler

C. single circuit system

D. multi pass system

E. direct cycle of coolant system

81. The thermodynamic efficiency of rotary compressor is based on_______________?
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A. isothermal compression

B. adiabatic compression

C. none of the above

D. polytropic compression

E. isentropic compression

82. Which is not identical for an atom and an isotope_________________?
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A. atomic number

B. position in periodic table

C. mass number

D. all of the above

E. chemical properties

83. The breeding gain in case of thermal breeder reactor as compared to fast breeder reactor is________________?
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A. higher/lower depending on the size of reactor

B. same

C. unity

D. higher

E. lower
84. The area of actual indicator diagram on an air compressor as compared to area of ideal indicator diagram is_____________________?
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A. unpredictable

B. more/less depending on compressor capacity

C. less

D. more

E. same

85. A centrifugal compressor works on the principle of__________________?
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A. generating pressure directly

B. centripetal action

C. conversion of pressure energy into kinetic energy

D. conversion of kinetic energy into pressure energy

E. combination of A. and D.

86. According to fan laws, for fans having constant wheel diameter, the air or gas capacity varies______________________?
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A. directly as fan speed

B. square of fan speed

C. cube of fan speed

D. square root of fan speed

E. none of the above

87. A closed gas turbine in which fuel is burnt directly in the air is not possible because of__________________?
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A. high specific volume

B. high friction losses

C. high pressure ratio

D. increasing gas temperature

E. paucity of 02
88. According to fan laws, at constant speed and capacity, the pressure and power vary_____________________?
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A. as square of density

B. inversely as square root of density

C. directly as the air or gas density

D. inversely as density

E. as square root of density

89. The specific output per kg mass flow rate of a gas turbine (having fixed efficiencies of compressor and turine and fixed higher and lower temperature) with increase in pressure ratio will___________________?
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A. increase first at fast rate and then slow

B. none of the above

C. decrease continuously

D. first increase, reach maximum and then decrease

E. increase first at slow rate and then fast

90. Reaction turbines are used for____________________?
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A. high head and high discharge

B. low head and high discharge

C. low head

D. high head and low discharge

E. high head

91. The ratio of outlet whirl velocity to blade velocity in case of centrifugal compressor is called__________________?
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A. velocity factor

B. blade effectiveness

C. velocity coefficient

D. slip factor
92. Temperature of gases at end of compression as compared to exhaust gases in a gas turbine is_________________?
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A. lower

B. higher

C. unpredictable

D. cant be compared

E. equal

93. Ram compression in turbojet involves____________________?
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A. increasing speed of incoming air

B. reduction of speed of incoming air and conversion of part of it into pressure energy

C. leakage losses

D. compression of inlet air

E. lost work

94. The effective power of gas turbines is increased by adding the following in compressor__________________?
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A. none of the above

B. nitrogen

C. ammonia and water vapour

D. carbon dioxide

E. hydrogen

95. Guide angle as per the aerofoil theory of Kaplan turbine blade design is defined as the angle between_________________?
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A. lift and resultant force

B. drag and resultant force

C. lift and tangential force

D. lift and drag

E. resultant force and tangential force

96. The operation of straightening a curved sheet metal, is known as____________________?
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A. coining

B. drawing

C. squeezing

D. planishing
97. A file removes the metal during___________________?
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A. both forward and return strokes

B. forward stroke

C. return stroke

D. none of these

98. Ferrite material is____________________?
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A. none of the above

B. the most fissionable material

C. basic raw material for nuclear plants

D. the basic fuel for nuclear paints

E. the material which absorbs neutrons and undergoes spontaneous changes leading to the formation of fissionable material
99. For speed above 3000 km/hour, it is more advantageous to use____________________?
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A. rockets

B. hydraulic jet propulsion

C. ram-jet engine

D. propellers

E. turbo-jet engine

100. If V, U and Vr represent the absolute velocity of fluid, velocity of blade, and relative velocity of fluid, and suffix i and o stand for entry and exit conditions, then in a rotary machine whose degree of reaction is unity______________?
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A. Vri=Vm

B. Vi=V0B

C. V,= U0

D. U,<V0

E. Vt>V0