The region between the separation streamline and the boundary surface of the solid body is known as
Wake
Drag
Lift
Boundary layer
Correct Answer :
A. Wake
Related Questions
Hydrometer is used to determine
Specific gravity of liquids
Specific gravity of solids
Specific gravity of gases
Relative humidity
The product of mass and acceleration of flowing liquid is called
Inertia force
Viscous force
Gravity force
Pressure force
In a broad-crested weir, the discharge is maximum if the head of water on the downstream side of weir is __________ the head of water on the upstream side of weir.
Equal to
One-third
Two-third
Three-fourth
An opening in the side of a tank or vessel such that the liquid surface with the tank is below the top edge of the opening, is called
Weir
Notch
Orifice
None of these
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
For hypersonic flow, the Mach number is
Unity
Greater than unity
Greater than 2
Greater than 4
An error of 1% in measuring head over the crest of the notch (H) will produce an error of __________ in discharge over a triangular notch,
1 %
1.5 %
2 %
2.5 %
The discharge through an external mouthpiece is given by (where a = Cross-sectional area of the mouthpiece, and H = Height of liquid above the mouthpiece)
0.855 a.√(2gH)
1.855 aH.√(2g)
1.585 a.√(2gH)
5.85 aH.√(2g)
A submerged body is said to be in a stable equilibrium, if its centre of gravity __________ the centre of buoyancy.
Coincides with
Lies below
Lies above
None of these
A glass tube of small diameter (d) is dipped in fluid. The height of rise or fall in the tube given by (where w = Specific weight of liquid, α = Angle of contact of the liquid surface, and σ = Surface tension)
4wd/σ cosα
σ cosα/4wd
4σ cosα/wd
wd/4σ cosα
A piece of metal of specific gravity 7 floats in mercury of specific gravity 13.6. What fraction of its volume is under mercury?
0.5
0.4
0.515
0.5
The coefficient of discharge for an external mouthpiece is
0.375
0.5
0.707
0.855
A flow in which each liquid particle has a definite path, and the paths of individual particles do not cross each other, is called
Steady flow
Uniform flow
Streamline flow
Turbulent flow
A point, in a compressible flow where the velocity of fluid is zero, is called
Critical point
Vena contracta
Stagnation point
None of these
Surface tension has the units of
Newton-sec/m
Newton-m/sec
Newton/m
Newton
The volume of a fluid __________ as the pressure increases.
Remains same
Decreases
Increases
None of these
A pipe of length more than double the diameter of orifice fitted externally or internally to the orifice is called a
Notch
Weir
Mouthpiece
Nozzle
The Metacentric heights of two floating bodies A and B are 1 m and 1.5 m respectively. Select the correct statement.
The bodies A and B have equal stability
The body A is more stable than body B
The body B is more stable than body A
The bodies A and B are unstable
Flow occurring in a pipeline when a valve is being opened is
Steady
Unsteady
Laminar
Vortex
Center of pressure compared to e.g. is
Above it
Below it
At same point
Above or below depending on area of body
The pressure in Pascals at a depth of 1 m below the free surface of a body of water will be equal to
1 Pa
91 Pa
981 Pa
9810 Pa
An open tank containing liquid is made to move from rest with a uniform acceleration. The angle 0 which the free surface of liquid makes with the horizontal is such that (where a = Horizontal acceleration of the tank, and g = Acceleration due to gravity)
tanθ = a/g
tanθ = 2 a/g
tanθ = a/2g
tanθ = a2/2g
A differential manometer is used to measure
Atmospheric pressure
Pressure in pipes and channels
Pressure in Venturimeter
Difference of pressures between two points in a pipe
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
A flow through an expanding tube at constant rate is called
Steady uniform flow
Steady non-uniform flow
Unsteady uniform flow
Unsteady non-uniform flow
The bulk modulus of elasticity with increase in pressure
Increases
Decreases
Remain constant
Increases first up to certain limit and then decreases
A flow in which the viscosity of fluid is dominating over the inertia force is called
Steady flow
Unsteady flow
Laminar flow
Turbulent flow
In an internal mouthpiece, if the jet after contraction does not touch the sides of the mouthpiece, then the mouthpiece is said to be
Running full
Running free
Partially running full
Partially running free
Non uniform flow occurs when
The direction and magnitude of the velocity at all points are identical
The velocity of successive fluid particles, at any point, is the same at successive periods of time
Velocity, depth, pressure, etc. change from point to point in the fluid flow.
The fluid particles move in plane or parallel planes and the streamline patterns are identical in each plane
Barometer is used to measure
Pressure in pipes, channels etc.
Atmospheric pressure
Very low pressure
Difference of pressure between two points