101. Capillary action is due to the
(a) surface tension
(b) cohesion of the liquid
(c) adhesion of the liquid molecules and the molecules on the surface of a solid
(d) all of the above
(e) none of the above.
Ans: d
103. Newton’s law of viscosity is a relationship between
(a) shear stress anctthejiate of angular dis¬tortion
(b) shear stress and viscosity
(c) shear stress, velocity and viscosity
(d) pressure, velocity and viscosity
(e) shear stress, pressure and rate of angular distortion.
Ans: a
104. The atmospheric pressure with rise in altitude decreases
(a) linearly
(b) first slowly and then steeply
(c) first steeply and then gradually
(d) unpredictable
(e) none of the above.
Ans: b
105. Pressure of the order of 10 torr can be measured by
(a) Bourdon tube
(b) Pirani Gauge
(c) micro-manometer
(d) ionisastion gauge
(e) McLeod gauge.
Ans: d
106. Operation of McLeod gauge used for low pressure measurement is based on the principle of
(a) gas law
(b) Boyle’s law
(c) Charle’s law
(d) Pascal’s law
(e) McLeod’s law.
Ans: b
107. An odd shaped body weighing 7.5 kg and occupying 0.01 m3 volume will be completely submerged in a fluid having specific gravity of
(a) 1
(b) 1.2
(c) 0.8
(d) 0.75
(e) 1.25
Ans: d
108. In an isothermal atmosphere, the pressure
(a) decreases linearly with elevation
(b) remains constant
(c) varies in the same way as the density
(d) increases exponentially with elevation
(e) unpredictable.
Ans: c
109. Mercury is often used in barometer because
(a) it is the best liquid
(b) the height of barometer will be less
(c) its vapour pressure is so low that it may be neglected
(d) both (b) and (c)
(e) it moves easily.
Ans: d
110. Barometer is used to measure
(a) pressure in pipes, channels etc.
(b) atmospheric pressure
(c) very low pressure
(d) difference of pressure between two points
(e) rain level.
Ans: b
111. Which of the following instrument can be used for measuring speed of a submarine moving in deep sea
(a) Venturimeter
(b) Orifice plate
(c) hot wire anemometer
(d) rotameter
(e) pitot tube.
Ans: e
112. Which of the following instrument can be used for measuring speed of an aeroplane
(a) Venturimeter
(b) Orifice plate
(c) hot wire anemometer
(d) rotameter
(e) pitot tube.
Ans: e
113. Piezometer is used to measure
(a) pressure in pipe, channels etc.
(b) atmospheric pressure
(c) very low pressures
(d) difference of pressure between two points
(e) flow.
Ans: c
114. Which of the following instruments is used to measure flow on the application of Bernoulli’s theorem
(a) Venturimeter
(b) Orifice plate
(c) nozzle
(d) pitot tube
(e) all of the above.
Ans: e
116. The speed of sound in a ideal gas varies directly as its
(a) pressure
(b) temperature
(c) density
(d) modulus of elasticity
(e) absolute temperature
Ans: e
119. Dynamic viscosity of most of the liquids with rise in temperature
(a) increases
(b) decreases
(a) remains unaffected
(d) unpredictable
(e) none of the above.
Ans: b
120. Dynamic viscosity of most of the gases with rise in temperature
(a) increases
(b) decreases
(c) remains unaffected
(d) unpredictable
(e) none of the above.
Ans: a
121. A metal with specific gravity of o floating in a fluid of same specific gravity a will
(a) sink to bottom
(b) float over fluid
(c) partly immersed
(d) be fully immersed with top surface at fluid surface
(e) none of the above.
Ans: d
123. Euler’s dimensionless number relates the following
(a) inertial force and gravity
(b) viscous force and inertial force
(c) viscous force and buoyancy force
(d) pressure force and inertial force
(e) pressure force and viscous force.
Ans: d
128. Manometer is used to measure
(a) pressure in pipes, channels etc.
(b) atmospheric pressure
(c) very low pressure
(d) difference of pressure between two points
(e) velocity.
Ans: a
129. Which of the following manometer has highest sensitivity
(a) U-tube with water
(b) inclined U-tube
(c) U-tube with mercury
(d) micro-manometer with water
(e) displacement type.
Ans: d
130. In order to increase sensitivity of U-tube manometer, one leg is usually inclined by angle 9. Sensitivity of inclined tube to sensitivity of U-tube is equal to
(a) sin 9
(b) sin 9
(c) cas9
(d) cos 9
(e) tan 9
Ans: b
131. Working principle of dead weight pressure gauge tester is based on
(a) Pascal’s law
(b) Dalton’s law of partial pressure
(c) Newton’s law of viscosity .
(d) Avogadro’s hypothesis
(e) Second law of thermodynamic.
Ans: a
132. The resultant of all normal pressures acts
(a) at e.g. of body
(b) at centre of pressure
(c) vertically upwards
(d) at metacentre
(e) vertically downwards.
Ans: c
133. Centre of pressure compared to e.g. is
(a) above it
(b) below it.
(c) at same point
(d) above or below depending on area of body
(e) none of the above.
Ans: b
134. Metacentric height is the distance between the metacentre and
(a) water surface
(b) centre of pressure
(c) centre of gravity
(d) centre of buoyancy
(e) none of the above.
Ans: c
135. The resultant upward pressure of the fluid on an immersed body due to its tendency to uplift the sub-merged body is called
(a) upthrust
(b) reaction
(c) buoyancy
(d) metacentre
(e) centre of pressure.
Ans: c
136. The centre of pressure of a surface subjected to fluid pressure is the point
(a) on the surface at which resultant pres-sure acts
(b) on the surface at which gravitational force acis
(c) at which all hydraulic forces meet
(d) similar to metacentre
(e) where pressure equivalent to hydraulic thrust will act.
Ans: a
137. Buoyant force is
(a) the resultant force acting on a floating body
(b) the resultant force on a body due to the fluid surrounding it
(c) equal to the volume of liquid dis-placed
(d) the force necessary to maintain equilibrium of a submerged body
(e) none of the above.
Ans: b
138. The horizontal component of buoyant force is
(a) negligible
(b) same as buoyant force
(c) zero
Ans: c
140. The line of action of the buoyant force acts through the
(a) centroid of the volume of fluid vertically above the body
(b) centre of the volume of floating body
(c) centre of gravity of any submerged body
(d) centriod of the displaced volume of fluid
(e) none of the above.
Ans: d
141. Centre of buoyancy is the
(a) centroid of the displaced volume of fluid
(b) centre of pressure of displaced volume
(c) e.g. of floating body
(d) does not exist
(e) none of the above.
Ans: a
142. A body floats in stable equilibrium
(a) when its meatcentric height is zero
(b) when the metancentre is above e.g.
(c) when its e.g. is below it’s centre of buoyancy
(d) metacentre has nothing to do with position of e.g. for determining stability
(e) none of the above.
Ans: b
143. A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specific gravity is
(a) 1
(b) 5
(c) 7
(d) 6
Ans: d