51. If mercury in a barometer is replaced by water, the height of 3.75 cm of mercury will be following cm of water
(a) 51 cm
(b) 50 cm
(c) 52 cm
(d) 52.2 cm
(e) 51.7 cm
Ans: a
52. Choose the wrong statement.
Alcohol is used in manometer, because
(a) its vapour pressure is low
(b) it provides suitable meniscus for the in-clined tube
(c) its density is less
(d) it provides longer length for a given pressure difference
(e) it provides accurate readings.
Ans: a
53. Increase in pressure at the outer edge of a drum of radius R due to rotation at corad/sec, full of liquid of density p will be
(a) pco2/2
(b) pco2/2/2
(c) 2pa2R2
(d) pa2R/2
(e) none of the above.
Ans: b
54. The property of fluid by virtue of which it offers resistance to shear is called
(a) surface tension
(b) adhesion
(c) cohesion
(d) viscosity
(e) all of the above.
Ans: d
55. Choose the wrong statement
(a) fluids are capable of flowing
(b) fluids conform to the shape of the containing vessels
(c) when in equilibrium, fluids cannot sustain tangential forces
(d) when in equilibrium, fluids can sustain shear forces
(e) fluids have some degree of compressibility and offer little resistance to form.
Ans: d
56. The density of water is 1000 kg/m3 at
(a) 0°C
(b) 0°K
(c) 4°C (d) 20°C
(e) all temperature.
Ans: c
57. If w is the specific weight of liquid and k the depth of any point from the surface, then pressure intensity at that point will be
(a) h
(b) wh
(c) w/h
(d) h/w
(e) h/wh
Ans: b
58. Choose the wrong statement
(a) 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 molecules
(c) Viscosity of liquids decreases with in-crease in temperature
(d) Viscosity of liquids is appreciably affected by change in pressure
(e) Viscosity is expressed as poise, stoke, or saybolt seconds.
Ans: d
59. The units of kinematic viscosity are
(a) metres2 per sec
(b) kg sec/metre
(c) newton-sec per metre
(d) newton-sec per metre
(e) none of the above.
Ans: a
60. The ratio of absolute viscosity to mass density is known as
(a) specific viscosity
(b) viscosity index
(c) kinematic viscosity
(d) coefficient of viscosity
(e) coefficient of compressibility.
Ans: c
61. Kinematic viscosity is equal to
(a) dynamic viscosity/density
(b) dynamicviscosity x density
(c) density/dynamic viscosity
(d) 1/dynamicviscosity x density
(e) same as dynamic viscosity.
Ans: a
62. Which of the following is the unit of kinematic viscosity
(a) pascal
(b) poise
(c) stoke
(d) faraday
(e) none of the above.
Ans: c
63. A one dimensional flow is one which
(a) is uniform flow
(b) is steady uniform flow
(c) takes place in straight lines
(d) involves zero transverse component of flow
(e) takes place in one dimension.
Ans: d
64. Alcohol is used in manometers because
(a) it has low vapour pressure
(b) it is clearly visible
(c) it has low surface tension
(d) it can provide longer column due to low density
(e) is provides suitable meniscus.
Ans: d
65. A pressure of 25 m of head of water is equal to
(a) 25 kN/m2
(b) 245 kN/m2
(c) 2500 kN/m2
(d) 2.5kN/m2
(e) 12.5 kN/m2
Ans: b
66. Specific weight of sea water is more that of pure water because it contains
(a) dissolved air
(b) dissolved salt
(c) suspended matter
(d) all of the above
(e) heavy water.
Ans: d
67. If 850 kg liquid occupies volume of one cubic meter, men 0.85 represents its
(a) specific weight
(b) specific mass
(c) specific gravity
(d) specific density
(e) none of the above.
Ans: c
69. Free surface of a liquid tends to contract to the smallest possible area due to force of
(a) surface tension
(b) viscosity
(c) friction
(d) cohesion
(e) adhesion.
Ans: a
70. A bucket of water is hanging from a spring balance. An iron piece is suspended into water without touching sides of bucket from another support. The spring balance reading will
(a) increase
(b) decrease
(c) remain same
(d) increase/decrease depending on depth of immersion
(e) unpredictable.
Ans: c
71. Falling drops of water become spheres due to the property of
(a) adhesion
(b) cohesion
(c) surface tension
(d) viscosity
(e) compressibility.
Ans: c
72. A liquid would wet the solid, if adhesion forces as compared to cohesion forces are
(a) less
(b) more
(c) equal
(d) less at low temperature and more at high temperature
(e) there is no such criterion.
Ans: b
73. If cohesion between molecules of a fluid is greater than adhesion between fluid and glass, then the free level of fluid in a dipped glass tube will be
(a) higher than the surface of liquid
(b) the same as the surface of liquid
(c) lower than the surface of liquid
(d) unpredictable
(e) none of the above.
Ans: c
74. The point in the immersed body through which the resultant pressure of the liquid may be taken to act is known as
(a) meta centre
(b) centre of pressure
(c) centre of buoyancy
(d) centre of gravity
(e) none of the above.
Ans: b
75. The total pressure on the surface of a vertical sluice gate 2 m x 1 m with its top 2 m surface being 0.5 m below the water level will be
(a) 500 kg
(b) 1000 kg
(c) 1500 kg
(d) 2000 kg
(e) 4000 kg
Ans: d