The fluid forces considered in the Navier Stokes equation are
Gravity, pressure and viscous
Gravity, pressure and turbulent
Pressure, viscous and turbulent
Gravity, viscous and turbulent
Correct Answer :
A. Gravity, pressure and viscous
Related Questions
A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specific gravity is
1
5
7
6
In a forced vortex, the velocity of flow everywhere within the fluid is
Maximum
Minimum
Zero
Nonzero finite
Kinematic viscosity is dependent upon
Pressure
Distance
Density
Flow
Differential manometer is used to measure
Pressure in pipes, channels etc.
Atmospheric pressure
Very low pressure
Difference of pressure between two points
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 flow in a pipe is turbulent when Reynold number is
Less than 2000
Between 2000 and 2800
More than 2800
None of these
Bernoulli equation deals with the law of conservation of
Mass
Momentum
Energy
Work
The theoretical velocity of jet at vena contracta is (where H = Head of water at vena contracta)
2gH
H × √(2g)
2g × √H
√(2gh)
The kinematic viscosity of an oil (in stokes) whose specific gravity is 0.95 and viscosity 0.011 poise, is
0.0116 stoke
0.116 stoke
0.0611 stoke
0.611 stoke
Choose the wrong statement
The horizontal component of the hydrostatic force on any surface is equal to the normal force on the vertical projection of the surface
The horizontal component acts through the center of pressure for the vertical projection
The vertical component of the hydrostatic force on any surface is equal to the weight of the volume of the liquid above the area
The vertical component passes through the center of pressure of the volume
The velocity of jet of water travelling out of opening in a tank filled with water is proportional to
Head of water (h)
h²
V/T
h/2
If a body floating in a liquid returns back to its original position, when given a small angular displacement, the body is said to be in
Neutral equilibrium
Stable equilibrium
Unstable equilibrium
None of these
The pressure of the liquid flowing through the divergent portion of a Venturimeter
Remains constant
Increases
Decreases
Depends upon mass of liquid
Reynolds number is significant in
Supersonics, as with projectile and jet propulsion
Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.
Simultaneous motion through two fluids where there is a surface of discontinuity, gravity forces, and wave making effect, as with ship's hulls
All of the above
The shear stress between the two liquid layers is __________ proportional to the distance between two layers.
Directly
Inversely
Both A and B
None of these
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)
The coefficient of discharge for an external mouthpiece is
0.375
0.5
0.707
0.855
In a venturi-flume, the flow takes place at
Atmospheric pressure
Gauge pressure
Absolute pressure
None of these
The specific gravity of an oil whose specific weight is 7.85 kN/m3, is
0.8
1
1.2
1.6
The value of coefficient of discharge is __________ the value of coefficient of velocity.
Less than
Same as
More than
None of these
The rise or depression of liquid in a tube due to surface tension will increase in size of tube will
Increase
Remain unaffected
May increase or decrease depending on the characteristics of liquid
Decrease
In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than
Frictional force
Viscosity
Surface friction
All of the above
The discharge through a channel of rectangular section will be maximum, if
Its depth is twice the breadth
Its breadth is twice the depth
Its depth is thrice the breadth
Its breadth is thrice the depth
A water tank contains 1.3 m deep water. The pressure exerted by the water per metre length of the tank is
2.89 kN
8.29 kN
9.28 kN
28.9 kN
For pipes, turbulent flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
The ratio of specific weight of a liquid to the specific weight of pure water at a standard temperature is called
Density of liquid
Specific gravity of liquid
Compressibility of liquid
Surface tension of liquid
The pressure measured with the help of a pressure gauge is called
Atmospheric pressure
Gauge pressure
Absolute pressure
Mean pressure
The centre of pressure acts __________ the centre of gravity of immersed surface.
At
Above
Below
None of these
The length of the divergent cone in a Venturimeter is __________ that of the convergent cone.
Equal to
Double
Three to four times
Five to six times
The equation of continuity holds good when the flow
Is steady
Is one dimensional
Velocity is uniform at all the cross sections
All of the above