For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
Correct Answer :
D. Shows erratic behaviour
Related Questions
A flow is called sub-sonic, if the Mach number is
Less than unity
Unity
Between 1 and 6
More than 6
A balloon lifting in air follows the following principle
Law of gravitation
Archimedes principle
Principle of buoyancy
All of the above
The absolute pressure is equal to
Gauge pressure + atmospheric pressure
Gauge pressure - atmospheric pressure
Atmospheric pressure - gauge pressure
Gauge pressure - vacuum pressure
The length of a liquid stream while flowing over a weir __________ at the ends of the sill.
Expands
Does not change
Contracts
None of these
The dynamic viscosity of the liquid __________ with rise in temperature.
Remain unaffected
Increases
Decreases
None of these
The pressure at a point 4 m below the free surface of water is
19.24 kPa
29.24 kPa
39.24 kPa
49.24 kPa
A flow through a long pipe at constant rate is called
Steady uniform flow
Steady non-uniform flow
Unsteady uniform flow
Unsteady non-uniform flow
Dynamic viscosity of most of the gases with rise in temperature
Increases
Decreases
Remain unaffected
Unpredictable
The total energy of a liquid particle in motion is equal to
Pressure energy + kinetic energy + potential energy
Pressure energy - (kinetic energy + potential energy)
Potential energy - (pressure energy + kinetic energy
Kinetic energy - (pressure energy + potential energy)
Uniform flow occurs when
The flow is steady
The flow is streamline
Size and shape of the cross section in a particular length remain constant
Size and cross section change uniformly along length
Choose the correct relationship
Specific gravity = gravity × density
Dynamic viscosity = kinematic viscosity × density
Gravity = specific gravity × density
Kinematic viscosity = dynamic viscosity × density
The hydraulic gradient line lies over the centre line of the pipe by an amount equal to the
Pressure head
Velocity head
Pressure head + velocity head
Pressure head - velocity head
The product of mass and acceleration of flowing liquid is called
Inertia force
Viscous force
Gravity force
Pressure force
The total energy line lies over the centre line of the pipe by an amount equal to
Pressure head
Velocity head
Pressure head + velocity head
Pressure head - velocity head
In an external mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to 0.89 times the height of the liquid, above the vena contracta.
Less than
More than
Equal to
None of these
The ratio of the inertia force to the elastic force is called
Reynold's number
Froude's number
Weber's number
Mach number
Reynold's number is the ratio of the inertia force to the
Surface tension force
Viscous force
Gravity force
Elastic force
With an increase in size of tube, the rise or depression of liquid in the tube due to surface tension will
Decrease
Increase
Remain unchanged
Depend upon the characteristics of liquid
The coefficient of discharge for an external mouthpiece depends upon
Velocity of liquid
Pressure of liquid
Area of mouthpiece
Length of mouthpiece
Ratio of inertia force to surface Jension is known as
Mach number
Froude number
Reynoldss number
Weber's number
The loss of head at exit of a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
The highest efficiency is obtained with a channel of __________ section.
Circular
Square
Rectangular
Trapezoidal
The tendency of a liquid surface to contract is due to the following property
Cohesion
Adhesion
Viscosity
Surface tension
The property of a fluid which enables it to resist tensile stress is known as
Compressibility
Surface tension
Cohesion
Adhesion
A flow through a long pipe at decreasing rate is called __________ uniform flow.
Steady
Unsteady
Both A and B
None of these
The discharge of a depressed nappe is 6 to 7 percent __________ that of a free nappe.
Less than
More than
Equal to
None of these
The discharge through a channel of trapezoidal section is maximum when
Width of channel at the top is equal to twice the width at the bottom
Depth of channel is equal to the width at the bottom
The sloping side is equal to half the width at the top
The sloping side is equal to the width at the bottom
The mercury does not wet the glass. This is due to the property of the liquid known as
Cohesion
Adhesion
Viscosity
Surface tension
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
1
1.2
0.8
0.75
A weir is said to be narrow-crested weir, if the width of the crest of the weir is __________ half the height of water above the weir crest.
Equal to
Less than
More than
None of these