Hydraulic and Fluid Machines - Pretest

7/27/2019 Hydraulic and Fluid Machines - Pretest

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HYDRAULIC AND FLUID MACHINES

1. Fluid is a substance thatA. cannot be subjected to shear forcesB. always expands until it fills any con-tainerC. has the same shear stress.at a point regardless of its motionD. cannot remain at rest under action of any shear force

2. Fluid is a substance which offers no resistance to change ofA. pressureB. flowC. shapeD. volume

3. Practical fluidsA. are viscousB. possess surface tensionC. are compressibleD. possess all the above properties

4. In a static fluidA. resistance to shear stress is smallB. fluid pressure is zeroC. linear deformation is smallD. only normal stresses can exist

5. A fluid is said to be ideal, if it isA. incompressibleB. inviscousC. viscous and incompressibleD. inviscous and incompressible.

6. An ideal flow of any fluid must fulfill the followingA. Newton's law of motionB. Newton's law of viscosityC. Pascal' lawD. Continuity equation

7. If no resistance is encountered by displacement, such a substance is known asA. fluidB. ideal fluidC. gasD. perfect solid

8. The volumetric change of the fluid caused by a resistance is known asA. volumetric strainB. volumetric indexC. compressibilityD. adhesion

9. LiquidsA. cannot be compressedB. occupy definite volumeC. are not affected by change in pressure and temperatureD. none of the above.

10.Density of water is maximum at


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A. 0CB. 0KC. 4CD. 100C

11.The value of mass density in kgsec/m4 for water at 0C isA. 1B. 1000C. 100D. 101.9

12.Property of a fluid by which its own molecules are attracted is calledA. adhesionB. cohesionC. viscosityD. compressibility

13.Mercury does not wet glass. This is due to property of liquid known asA. adhesionB. cohesionC. surface tensionD. viscosity

14.The property of a fluid which enables it to resist tensile stress is known asA. compressibilityB. surface tensionC. cohesionD. adhesion

15.Property of a fluid by which molecules of different kinds of fluids are attracted to each other iscalled

A. adhesionB. cohesionC.

viscosity

D. compressibility16.The specific weight of water is 1000 kg/m3

A. at normal pressure of 760 mmB. at 4C temperatureC. at mean sea levelD. all the above

17.Specific weight of water in S.I. units is equal toA. 1000 N/m3B. 10000 N/m3C. 9.81 x 103 N/m3D. 9.81 x 106 N/m3

18.When the flow parameters at any given instant remain same at every point, then flow is said to beA. quasi staticB. steady stateC. laminarD. uniform

19.Which of the following is dimensionlessA. specific weightB. specific volume


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C. specific speedD. specific gravity

20.The normal stress in a fluid will be constant in all directions at a point only ifA. it is incompressibleB. it is at rest.C. it has uniform viscosityD. it has zero viscosity

21.The pressure at a point in a fluid will not be same in all the directions when the fluid isA. movingB. viscousC. viscous and staticD. viscous and moving.

22.An object having 10 kg mass weighs 9.81 kg on a spring balance. The value of 'g' at this place isA. 10 m/sec2B. 9.81 m/sec2C. 10.2/m sec2D. 9.75 m/sec2

23.The tendency of a liquid surface to contract is due to the following propertyA. cohesionB. adhesionC. viscosityD. surface tension

24.The surface tension of mercury at normal temperature compared to that of water isA. moreB. lessC. sameD. more or less depending on size of glass tube

25.A perfect gasA.

has constant viscosity

B. has zero viscosityC. is incompressibleD. none of the above

26.For very great pressures, viscosity of moss gases and liquidsA. remains sameB. increasesC. decreasesD. shows erratic behavior

27.A fluid in equilibrium can't sustainA. tensile stressB. compressive stressC. shear stressD. bending stress

28.Viscosity of water in comparison to mercury isA. higherB. lowerC. sameD. higher/lower depending on temperature

29.The bulk modulus of elasticity with increase in pressure


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A. increasesB. decreasesC. remains constantD. increases first up to certain limit and then decreases

30.The bulk modulus of elasticityA. has the dimensions of 1/pressureB. increases with pressureC. is large when fluid is more compressibleD. is independent of pressure and viscosity

31.A balloon lifting in air follows the following principleA. law of gravitationB. Archimedes principleC. principle of buoyancyD. all of the above

32.The value of the coefficient of compressibility for water at ordinary pressure and temperature inkg/cm is equal to

A. 1000B. 2100C. 2700D. 21,000.

33.The increase of temperature results inA. increase in viscosity of gasB. increase in viscosity of liquidC. decrease in viscosity of gasD. decrease in viscosity of liquid

34.Surface tensionA. acts in the plane of the interface normal to any line in the surfaceB. is also known as capillarityC.

is a function of the curvature of the interface

D. decreases with fall in temperature35.The stress-strain relation of the newtonian fluid is

A. linearB. parabolicC. hyperbolicD. inverse type

36.A liquid compressed in cylinder has a volume of 0.04 m3 at 50 kg/cm2 and a volume of 0.039 m3 at150 kg/cm

2. The bulk modulus of elasticity of liquid is

A. 400 kg/cm2B. 4000 kg/cm2C. 40 x 105 kg/cm2D. 40 x 106 kg/cm2

37.The units of viscosity areA. metres2 per secB. kg sec/metreC. newton-sec per metre2D. newton-sec per metre

38.Kinematic viscosity is dependent uponA. pressure


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B. distanceC. levelD. density.

39.Units of surface tension areA. energy/unit areaB. distanceC. both of the aboveD. it has no units

40.Which of the following meters is not associated with viscosityA. Red woodB. Say boltC. EnglerD. Orsat

41.Choose the correct relationshipA. specific gravity = gravity x densityB. dynamic viscosity = kinematic viscosity x densityC. gravity = specific gravity x densityD. kinematic viscosity = dynamic viscosity x density

42.For manometer, a better liquid combination is one havingA. higher surface tensionB. lower surface tensionC. surface tension is no criterionD. high density and viscosity

43. If mercury in a barometer is replaced by water, the height of 3.75 cm of mercury will be followingcm of water

A. 51 cmB. 50 cmC. 52 cmD.

52.2 cm

44.Choose the wrong statement. Alcohol is used in manometer, becauseA. its vapour pressure is lowB. it provides suitable meniscus for the inclined tubeC. its density is lessD. it provides longer length for a given pressure difference

45. Increase in pressure at the outer edge of a drum of radius R due to rotation at rad/sec, full ofliquid of densitywill be

A. 2/g2B. 2R2/2C. 22R2D.

2

R/246.The property of fluid by virtue of which it offers resistance to shear is calledA. surface tensionB. adhesionC. cohesionD. viscosity

47.Choose the wrong statementA. fluids are capable of flowing


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B. fluids conform to the shape of the containing vesselsC. when in equilibrium, fluids cannot sustain tangential forcesD. when in equilibrium, fluids can sustain shear forces

48.The density of water is 1000 kg/m3 atA. 0CB. 0KC. 4CD. 20C

49. Ifw is the specific weight of liquid and h the depth of any point from the surface, then pressureintensity at that point will be

A. hB. whC. w/hD. h/w

50.Choose the wrong statementA. Viscosity of a fluid is that property which determines the amount of its resistance to a shearing

force

B. Viscosity is due primarily to interaction between fluid moleculesC. Viscosity of liquids decreases with in-crease in temperatureD. Viscosity of liquids is appreciably affected by change in pressure

51.The units of kinematic viscosity areA. metres2 per secB. kg sec/metreC. newton-sec per metreD. newton-sec - metre

52.The ratio of absolute viscosity to mass density is known asA. specific viscosityB. viscosity indexC.

kinematic viscosity

D. coefficient of viscosity53.Kinematic viscosity is equal to

A. dynamic viscosity/densityB. dynamicviscosity x densityC. density/dynamic viscosityD. 1/dynamicviscosity x density

54.Which of the following is the unit of kinematic viscosityA. pascalB. poiseC. stokeD. faraday

55.A one dimensional flow is one whichA. is uniform flowB. is steady uniform flowC. takes place in straight linesD. involves zero transverse component of flow

56.Alcohol is used in manometers becauseA. it has low vapour pressureB. it is clearly visible


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C. it has low surface tensionD. it can provide longer column due to low density

57.A pressure of 25 m of head of water is equal toA. 25 kN/m2B. 245 kN/m2C. 2500 kN/m2D. 2.5kN/m2

58.Specific weight of sea water is more that of pure water because it containsA. dissolved airB. dissolved saltC. suspended matterD. all of the above

59. If 850 kg liquid occupies volume of one cubic meter, men 0.85 represents itsA. specific weightB. specific massC. specific gravityD. specific density

60.Free surface of a liquid tends to contract to the smallest possible area due to force ofA. surface tensionB. viscosityC. frictionD. cohesion

61.A bucket of water is hanging from a spring balance. An iron piece is suspended into water withouttouching sides of bucket from another support. The spring balance reading will

A. increaseB. decreaseC. remain sameD.

increase/decrease depending on depth of immersion

62.Falling drops of water become spheres due to the property ofA. adhesionB. cohesionC. surface tensionD. viscosity

63.A liquid would wet the solid, if adhesion forces as compared to cohesion forces areA. lessB. moreC. equalD. less at low temperature and more at high temperature

64. If cohesion between molecules of a fluid is greater than adhesion between fluid and glass, then thefree level of fluid in a dipped glass tube will be

A. higher than the surface of liquidB. the same as the surface of liquidC. lower than the surface of liquidD. unpredictable

65.The point in the immersed body through which the resultant pressure of the liquid may be taken toact is known as

A. meta centre


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B. centre of pressureC. centre of buoyancyD. centre of gravity

66.The total pressure on the surface of a vertical sluice gate 2 m x 1 m with its top 2 m surface being 0.5m below the water level will be

A. 500 kgB. 1000 kgC. 1500 kgD. 2000 kg

67.The resultant upward pressure of a fluid on a floating body is equal to the weight of the fluiddisplaced by the body. This definition is according to

A. BuoyancyB. Equilibrium of a floating bodyC. Archimedes' principleD. Bernoulli's theorem

68.The resultant upward pressure of the fluid on an immersed body is calledA. upthrustB. buoyancyC. centre of pressureD. all the above are correct

69.The conditions for the stable equilibrium of a floating body areA. the meta-centre should lie above the centre of gravityB. the centre of buoyancy and the centre of gravity must lie on the same vertical lineC. a righting couple should be formedD. all the above are correct

70.Poise is the unit ofA. surface tensionB. capillarityC.

viscosity

D. shear stress in fluids71.Metacentric height is given as the distance between

A. the centre of gravity of the body and the meta centreB. the centre of gravity of the body and the centre of buoyancyC. the centre of gravity of the body and the centre of pressureD. centre of buoyancy and metacentre

72.The buoyancy depends onA. mass of liquid displacedB. viscosity of the liquidC. pressure of the liquid displacedD. depth of immersion

73. The centre of gravity of the volume of the liquid displaced by an immersed body is calledA. meta-centreB. centre of pressureC. centre of buoyancyD. centre of gravity

74.A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction ofit volume is under mercury?

A. the metal piece will simply float over the mercury


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B. the metal piece will be immersed in mercury by halfC. whole of the metal piece will be immersed with its top surface just at mercury levelD. metal piece will sink to the bottom

75.The angle of contact in case of a liquid depends uponA. the nature of the liquid and the solidB. the material which exists above the free surface of the liquidC. both of the aboveD. any one of the above

76.Free surface of a liquid behaves like a sheet and tends to contract to smallest possible area due tothe

A. force of adhesionB. force of cohesionC. force of frictionD. force of diffusionE. none of die above.

77.Rain drops are spherical because ofA. viscosityB. air resistanceC. surface tension forcesD. atmospheric pressure

78.Surface energy per unit area of a surface is numerically equal to ..A. atmospheric pressureB. surface tensionC. force of adhesionD. force of cohesion

79.The capillary rise at 20C in a clean glass tube of 1 mm bore containing water is approximatelyA. 1 mmB. 5 mmC.

10 mm

D. 30 mm80. If the surface of liquid is convex, men

A. cohesion pressure is negligibleB. cohesion pressure is decreasedC. cohesion pressure is increasedD. there is no cohesion pressure

81.To avoid vaporisation in the pipe line, the pipe line over the ridge is laid such that it is not more thanA. 2.4 m above the hydraulic gradientB. 6.4 m above the hydraulic gradientC. 10.0 m above the hydraulic gradientD. 5.0 above the hydraulic gradient

82.To avoid an interruption in the flow of a syphon, an air vessel is providedA. at the inletB. at the outletC. at the summitD. none of the above.

83.The vapour pressure over the concave surface isA. less man the vapour pressure over the plane surfaceB. equal to the vapour pressure over the plane surface


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C. greater than the vapour pressure over the plane surfaceD. zero

84.The property by virtue of which a liquid opposes relative motion between its different layers iscalled

A. surface tensionB. co-efficient of viscosityC. viscosityD. osmosis

85.The process of diffusion of one liquid into the other through a semi-permeable membrane is calledA. viscosityB. osmosisC. surface tensionD. cohesion

86.The units of dynamic or absolute viscosity areA. metres2 per secB. kg sec/metreC. newton-sec per metreD. newton-sec2 per metre

87.The continuity equation is connected withA. viscous/unviscous fluidsB. compressibility of fluidsC. conservation of massD. steady/unsteady flow

88. The rise or depression of liquid in a tube due to surface tension with increase in size of tube willA. increaseB. remain unaffectedC. may increase or decrease depending on the characteristics of liquidD.

decrease

89.Liquids transmit pressure equally in all the directions. This is according toA. Boyle's lawB. Archimedes principleC. Pascal's lawD. Newton's formula

90.Capillary action is due to theA. surface tensionB. cohesion of the liquidC. adhesion of the liquid molecules and the molecules on the surface of a solidD. all of the above

91.Newton's law of viscosity is a relationship betweenA. shear stress and the rate of angular distortionB. shear stress and viscosityC. shear stress, velocity and viscosityD. pressure, velocity and viscosity

92.The atmospheric pressure with rise in altitude decreasesA. linearlyB. first slowly and then steeplyC. first steeply and then gradually


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D. unpredictable93.Pressure of the order of 10-10 torr can be measured by

A. Bourdon tubeB. Pirani GaugeC. micro-manometerD. ionization gauge

94.Operation of McLeod gauge used for low pressure measurement is based on the principle ofA. gas lawB. Boyle's lawC. Charles lawD. Pascal's law

95.An odd shaped body weighing 7.5 kg and occupying 0.01 m3 volume will be completely submergedin a fluid having specific gravity of

A. 1B. 1.2C. 0.8D. 0.75

96. In an isothermal atmosphere, the pressureA. decreases linearly with elevationB. remains constantC. varies in the same way as the densityD. increases exponentially with elevation

97.Mercury is often used in barometer becauseA. it is the best liquidB. the height of barometer will be lessC. its vapour pressure is so low that it may be neglectedD. both (b) and (c)

98.Barometer is used to measureA. pressure in pipes, channels etc.B. atmospheric pressureC. very low pressureD. difference of pressure between two points

99.Which of the following instrument can be used for measuring speed of an aeroplaneA. VenturimeterB. Orifice plateC. hot wire anemometerD. Pitot tube.

100. Piezometer is used to measureA. pressure in pipe, channels etc.B. atmospheric pressureC. very low pressuresD. difference of pressure between two points

101. Which of the following instruments is used to measure flow on the application of Bernoulli'stheorem

A. VenturimeterB. Orifice plateC. nozzle


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D. all of the above.102. The speed of sound in a ideal gas varies directly as its

A. pressureB. temperatureC. densityD. absolute temperature

103. Dynamic viscosity of most of the liquids with rise in temperatureA. increasesB. decreasesC. remains unaffectedD. unpredictable

104. Dynamic viscosity of most of the gases with rise in temperatureA. increasesB. decreasesC. remains unaffectedD. unpredictable

105. A metal with specific gravity of o floating in a fluid of same specific gravity a willA. sink to bottomB. float over fluidC. partly immersedD. be fully immersed with top surface at fluid surface

106. Euler's dimensionless number relates the followingA. inertial force and gravityB. viscous force and inertial forceC. viscous force and buoyancy forceD. pressure force and inertial force

107. Manometer is used to measureA. pressure in pipes, channels etc.B.

atmospheric pressure

C. very low pressureD. difference of pressure between two points

108. Which of the following manometer has highest sensitivityA. U-tube with waterB. inclined U-tubeC. U-tube with mercuryD. micro-manometer with water

109. Working principle of dead weight pressure gauge tester is based onA. Pascal's lawB. Dalton's law of partial pressureC. Newton's law of viscosity .D. Avogadro's hypothesis

110. The resultant of all normal pressures actsA. at e.g. of bodyB. at centre of pressureC. vertically upwardsD. at metacentre

111. Centre of pressure compared to e.g. isA. above it


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B. below it.C. at same pointD. above or below depending on area of body

112. Metacentric height is the distance between the metacentre andA. water surfaceB. centre of pressureC. centre of gravityD. centre of buoyancy

113. The resultant upward pressure of the fluid on an immersed body due to its tendency to upliftthe sub-merged body is called

A. upthrustB. reactionC. buoyancyD. metacentre

114. The centre of pressure of a surface subjected to fluid pressure is the pointA. on the surface at which resultant pressure actsB. on the surface at which gravitational force actsC. at which all hydraulic forces meetD. similar to metacentre

115. Buoyant force isA. the resultant force acting on a floating bodyB. the resultant force on a body due to the fluid surrounding itC. equal to the volume of liquid dis-placedD. the force necessary to maintain equilibrium of a submerged body

116. The horizontal component of buoyant force isA. negligibleB. same as buoyant forceC. zeroD.

none of the above

117. The line of action of the buoyant force acts through theA. centroid of the volume of fluid vertically above the bodyB. centre of the volume of floating bodyC. centre of gravity of any submerged bodyD. centroid of the displaced volume of fluid

118. Centre of buoyancy is theA. centroid of the displaced volume of fluidB. centre of pressure of displaced volumeC. e.g. of floating 'bodyD. does not exist

119. A body floats in stable equilibriumA. when its metacentric height is zeroB. when the metacentre is above c.g.C. when its e.g. is below it's centre of buoyancyD. metacentre has nothing to do with position of e.g. for determining stability

120. A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specificgravity is

A. 1B. 5


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C. 7D. 6

121. The total pressure force on a plane area is equal to the area multiplied by the intensity ofpressure at the centroid, if

A. the area is horizontalB. the area is verticalC. the area is inclinedD. all of the above

122. A square surface 3 m x 3 m lies in a vertical line in water pipe its upper edge at water surface.The hydrostatic force on square surface is

A. 9,000 kgB. 13,500 kgC. 18,000 kgD. 27,000 kg

123. The depth of the centre of pressure on a vertical rectangular gate 8 m wide and 6 m high, whenthe water surface coincides with the top of the gate, is

A. 2.4 mB. 3.0 mC. 4.0 mD. 2.5 m

124. If the atmospheric pressure on the surface of an oil tank (sp. gr. 0.8) is 0.2 kg/cm2, the pressureat a depth of 50 m below the oil surface will be

A. 2 metres of water columnB. 3 metres of water columnC. 5 metres of water columnD. 6 metres of water Column

125. Metacentre is the point of intersection ofA. vertical upward force through c.g. of body and centre line of bodyB.

buoyant force and the centre line of body

C. midpoint between e.g. and centre of buoyancyD. all of the above

126. Choose the wrong statementA. The horizontal component of the hydro-static force on any surface is equal to the normal force

on the vertical projection of the surface

B. The horizontal component acts through the centre of pressure for the vertical projectionC. The vertical component of the hydrostatic force on any surface is equal to the weight of the

volume of the liquid above the area

D. The vertical component passes through the centre of pressure of the volume127. For a body floating in a liquid the normal pressure exerted by the liquid acts at

A. bottom surface of the bodyB. c.g. of the bodyC. metacentreD. all points on the surface of the body

128. Choose the wrong statementA. any weight, floating or immersed in a liquid, is acted upon by a buoyant forceB. Buoyant force is equal to the weight of the liquid displacedC. The point through which buoyant force acts, is called the centre of buoyancyD. Centre of buoyancy is located above the centre of gravity of the displaced liquid


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129. According to the principle of buoyancy a body totally or partially immersed in a fluid will belifted up by a force equal to

A. the weight of the bodyB. more than the weight of the bodyC. less than the weight of the bodyD. weight of the fluid displaced by the body

130. When a body floating in a liquid, is displaced slightly, it oscillates aboutA. c.g. of bodyB. centre of pressureC. centre of buoyancyD. metacentre

131. Buoyant force isA. resultant force acting on a floating bodyB. equal to the volume of liquid displacedC. force necessary to keep a body in equilibriumD. the resultant force on a body due to the fluid surrounding it

132. Ratio of inertia force to surface tension is known asA. Mach numberB. Froude numberC. Reynolds numberD. Weber's number

133. A ship whose hull length is 100 m is to travel at 10 m/sec. For dynamic similarity, at whatvelocity should a 1:25 model be towed through water?

A. 10 m/secB. 25 m/secC. 2 m/secD. 50 m/sec

134.

A model of a reservior is drained in 4 mts by opening the sluice gate. The model scale is 1: 225.How long should it take to empty the prototype?

A. 900 minutesB. 4 minutesC. 4 x (225)3/2 minutesD. 4 x minutes.

135. A model of torpedo is tested in a towing tank at a velocity of 25 m/sec. The prototype isexpected to attain a velocity of 5 m/sec. What model scale has been used?

A. 1 : 5B. 1 : 2.5C. 1 : 25D.

1:5

136. Ratio of inertia force to elastic force is known asA. Mach numberB. Froude numberC. Reynolds numberD. Weber's number

137. For a floating body to be in stable equilibrium, its metacentre should beA. below the centre of gravityB. below the centre of buoyancy


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C. above the centre of buoyancyD. above the centre of gravity.

138. For a floating body to be in equilibriumA. meta centre should be above c.g.B. centre of buoyancy and e.g. must lie on same vertical planeC. a righting couple should be formedD. all of the above

139. The two important forces for a floating body areA. buoyancy, gravityB. buoyancy, pressureC. buoyancy, inertialD. inertial, gravity

140. Choose the wrong statementA. The centre of buoyancy is located at the centre of gravity of the displaced liquidB. For stability of a submerged body, the centre of gravity of body must lie directly below the

centre of buoyancy

C. If e.g. and centre of buoyancy coincide, the submerged body must lie at neutral equilibrium forall positions

D. All floating bodies are stable.141. Centre of pressure on an inclined plane is

A. at the centroidB. above the centroidC. below the centroidD. at metacentre

142. An open vessel of water is accelerated up an inclined plane. The free water surface willA. be horizontalB. make an angle in direction of inclination of inclined planeC. make an angle in opposite direction to inclination of inclined planeD.

any one of above is possible

143. The line of action of the buoyant force acts through the centroid of theA. submerged bodyB. volume of the floating bodyC. volume of the fluid vertically above the bodyD. displaced volume of the fluid

144. Resultant pressure of the liquid in the case of an immersed body acts throughA. centre of gravityB. centre of pressureC. metacentreD. centre of buoyancy

145. The centre of gravity of the volume of the liquid displaced by an immersed body is calledA. centre of gravityB. centre of pressureC. metacentreD. centre of buoyancy

146. Differential monometer is used to measureA. pressure in pipes, channels etc.B. atmospheric pressureC. very low pressure


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D. difference of pressure between two points147. The pressure in the air space above an oil (sp. gr. 0.8) surface in a tank is 0.1 kg/cm2. The

pressure at 2.5 m below the oil surface will be

A. 2 metres of water columnB. 3 metres of water columnC. 3.5 metres of water columnD. 4 m of water column

148. The time oscillation of a floating body with increase in metacentric height will beA. sameB. higherC. lowerD. lower/higher depending on weight of body

149. In an immersed body, centre of pressure isA. at the centre of gravityB. above the centre of gravityC. below be centre of gravityD. could be above or below e.g. depending on density of body and liquid

150. The normal stress is same in all directions at a point in a fluidA. only when the fluid is frictionlessB. only when the fluid is incompressible and has zero viscosityC. when there is no motion of one fluid layer relative to an adjacent layerD. irrespective of the motion of one fluid layer relative to an adjacent layer

151. Select the correct statementA. Local atmospheric pressure depends upon elevation of locality onlyB. Standard atmospheric pressure is the mean local atmospheric pressure at sea levelC. Local atmospheric pressure is always below standard atmospheric pressureD. A barometer reads the difference be-tween local and standard atmospheric pressure

152.

For measuring flow by a venturimeter, if should be installed inA. vertical lineB. horizontal lineC. inclined line with flow downwardD. in any direction and in any location.

153. Total pressure on a 1 m x 1 m gate immersed vertically at a depth of 2 m below the free watersurface will be

A. 1000 kgB. 4000 kgC. 2000 kgD. 8000 kg

154. Hot wire anemometer is used to measureA. pressure in gasesB. liquid dischargeC. pressure in liquidsD. gas velocities

155. Rotameter is a device used to measureA. absolute pressureB. velocity of fluidC. flow


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D. rotation156. Flow of water in a pipe about 3 metres in diameter can be measured by

A. orifice plateB. ventureC. rotameterD. pitot tube

157. True one-dimensional flow occurs whenA. the direction and magnitude of the velocity at all points are identicalB. the velocity of successive fluid particles, at any point, is the same at successive periods of timeC. the magnitude and direction of the velocity do not change from point to point in the fluidD. the fluid particles move in plane or parallel planes and the streamline pat-terns are

158. An ideal flow of any fluid must satisfyA. Pascal lawB. Newton's law of viscosityC. boundary layer theoryD. continuity equation

159. In the case of steady flow of a fluid, the acceleration of any fluid particle isA. constantB. variableC. zeroD. zero under limiting conditions

160. Non uniform flow occurs whenA. the velocity of successive fluid particles, at any point, is the same at successive periods of timeB. the magnitude aricf direction of the velocity do not change from point to point in the fluidC. the fluid particles move in plane or parallel planes and the streamline patterns are identical in

each plane

D. velocity, depth, pressure, etc. change from point to point in the fluid flow.161. During the opening of a valve in a pipe line, the flow is

A.

steadyB. unsteadyC. uniformD. laminar

162. Uniform flow occurs whenA. the flow is steadyB. the flow is streamlineC. size and shape of the cross section in a particular length remain constantD. size and cross section change uniformly along length

163. Gradually varied flow isA. steady uniformB. non-steady non-uniformC. non-steady uniformD. steady non-uniform

164. Steady flow occurs whenA. the direction and magnitude of the velocity at all points are identicalB. the velocity of successive fluid particles, at any point, is the same at successive periods of timeC. the magnitude and direction of the velocity do not change from point to point in the fluidD. the fluid particles move in plane or parallel planes and the streamline patterns are identical in

each plane


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165. The flow which neglects changes in a transverse direction is known asA. one dimensional flowB. uniform flowC. steady flowD. turbulent flow

166. The flow in which each liquid particle has a definite path and their paths do not cross eachother is called

A. one dimensional flowB. uniform flowC. steady flowD. streamline flow.

167. The flow in which conditions do not change with time at any point, is known asA. one dimensional flowB. uniform flowC. steady flowD. turbulent flow

168. The flow in which the velocity vector is identical in magnitude and direction at every point, forany given instant, is known asA. one dimensional flowB. uniform flowC. steady flowD. turbulent flow

169. The flow in which the particles of a fluid attain such velocities that vary from point to point inmagnitude and direction as well as from instant to instant, is known as

A. one dimensional flowB. uniform flowC. steady flowD. turbulent flow

170.

Flow occurring in a pipeline when a valve is being opened isA. steadyB. unsteadyC. laminarD. vortex

171. General energy equation holds forA. steady flowB. turbulent flowC. laminar flowD. non-uniform flow

172. A streamline is defined as the lineA. parallel to central axis flowB. parallel to outer surface of pipeC. of equal velocity in a flowD. along which the pressure drop is uniform

173. Two dimensional flow occurs whenA. the direction and magnitude of the velocity at all points are identicalB. the velocity of successive fluid particles, at any point, is the same at successive periods of timeC. the magnitude and direction of the velocity do not change from point to point in the fluid


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D. the fluid particles move in plane or parallel planes and the streamline patterns are identical ineach plane

174. A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6. What fraction ofits volume is under mercury ?

A. 0.5B. 0.4C. 0.515D. 0.5

175. A piece of wood having weight 5 kg floats in water with 60% of its volume under the liquid. Thespecific gravity of wood is

A. 0.83B. 0.6C. 0.4D. 0.3

176. In a free vortex motion, the radial component of velocity everywhere isA. maximumB. minimumC. zeroD. non-zero and finite

177. In a forced vortex, the velocity of flow everywhere within the fluid isA. maximumB. minimumC. zeroD. non-zero finite

178. The region between the separation streamline and the boundary surface of the solid body isknown as

A. wakeB. dragC.

lift

D. boundary layer179. For hypersonic flow, the Mach number is

A. unityB. greater than unityC. greater than 2D. greater than 4

180. The upper surface of a weir over which water flows is known isA. crestB. nappeC. sillD. weir top

181. Normal depth in open channel flow is the depth of flow corresponding toA. steady flowB. unsteady flowC. laminar flowD. uniform flow

182. Uniform flow occurs whenA. the direction and magnitude of the velocity at all points are identicalB. the velocity of successive fluid particles, at any point, is the same at successive periods of time


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C. the magnitude and direction of the velocity do not change from point to point in the fluidD. the fluid particles move in plane or parallel planes and the streamline patterns are identical in

each plane

183. Pitot tube is used for measurement ofA. pressureB. flowC. velocityD. discharge

184. Hydrometer is used to determineA. specific gravity of liquidsB. specific gravity of solidsC. specific gravity of gasesD. relative humidity

185. The total energy of each particle at various places in the case of perfect incompressible fluidflowing in continuous stream

A. keeps on increasingB. keeps on decreasingC. remains constantD. may increase/decrease

186. According to Bernoulli's equation for steady ideal fluid flowA. principle of conservation of mass holdsB. velocity and pressure are inversely proportionalC. total energy is constant throughoutD. the energy is constant along a stream-line but may vary across streamlines

187. The equation of continuity holds good when the flowA. is steadyB. is one dimensionalC. velocity is uniform at all the cross sectionsD.

all of the above

188. Mach number is significant inA. supersonics, as with projectiles and jet propulsionB. full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.C. simultaneous motion through two fluids where there is a surface of discontinuity, gravity force,

and wave making effects, as with ship's hulls

D. all of the above189. Froude number is significant in

A. supersonics, as with projectile and jet propulsionB. full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.C. simultaneous motion through two fluids where there is a surface of discontinuity, gravity

forces, and wave making effect, as with ship's hulls

D. all of the above190. All the terms of energy in Bernoulli's equation have dimension of

A. energyB. workC. massD. length

191. Reynolds number is significant inA. supersonics, as with projectile and jet propulsion


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B. full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.C. simultaneous motion through two fluids where there is a surface of discontinuity, gravity forces,

and wave making effect, as with ship's hulls

D. all of the above192. The fluid forces considered in the Navier Stokes equation are

A. gravity, pressure and viscousB. gravity, pressure and turbulentC. pressure, viscous and turbulentD. gravity, viscous and turbulent

193. A large Reynolds number is indication ofA. smooth and streamline flowB. laminar flowC. turbulent flowD. highly turbulent flow.

194. For pipes, laminar flow occurs when Roynolds number isA. less than 2000B. between 2000 and 4000C. more than 4000D. less than 4000

195. In order that flow takes place between two points in a pipeline, the differential pressurebetween these points must be more than

A. frictional forceB. viscosityC. surface frictionD. all of the above

196. At the centre line of a pipe flowing under pressure where the velocity gradient is zero, the shearstress will be

A. minimumB.

maximum

C. zeroD. could be any value.

197. The pressure in Pascals at a depth of 1 m below the free surface of a body of water will be equalto

A. 1 PaB. 98.1PaC. 981 PaD. 9810 Pa

198. Two pipe systems can be said to be equivalent, when the following quantities are sameA. friction loss and flowB. length and diameterC. flow and lengthD. friction factor and diameter

199. For pipes, turbulent flow occurs when Reynolds number isA. less than 2000B. between 2000 and 4000C. more than 4000D. less than 4000

200. Bernoulli equation deals with the law of conservation of


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A. massB. momentumC. energyD. work

201. A hydraulic press has a ram of 15 cm diameter and plunger of 1.5 cm. It is required to lift aweight of 1 tonne. The force required on plunger is equal to

A. 10 kgB. 100 kgC. 1000 kgD. 1 kg

202. Cavitation is caused byA. high velocityB. high pressureC. weak materialD. low pressure

203. Cavitation will begin whenA. the pressure at any location reaches an absolute pressure equal to the saturated vapour

pressure of the liquidB. pressure becomes more than critical pressureC. flow is increasedD. pressure is increased

204. Principle of similitude forms the basis ofA. comparing two identical equipmentsB. designing models so that the result can be converted to prototypesC. comparing similarity between design and actual equipmentD. hydraulic designs

205. For similarity, in addition to models being geometrically similar to prototype, the following inboth cases should also be equal

A.

ratio of inertial force to force due to viscosityB. ratio of inertial force to force due to gravitationC. ratio of inertial force to force due to surface tensionD. all the four ratios of inertial force to force due to viscosity, gravitation, surface tension, and

elasticity

END

Hydraulic and Fluid Machines - Pretest

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