The upper surface of a weir over which water flows is known is
Crest
Nappy
Sill
Weir top
Correct Answer :
C. Sill
Related Questions
In an internal mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to height of the liquid above the vena contracta.
Less than
More than
Equal to
None of these
The value of coefficient of velocity for a sharp edged orifice __________ with the head of water.
Decreases
Increases
Remain same
None of these
The product of mass and acceleration of flowing liquid is called
Inertia force
Viscous force
Gravity force
Pressure force
A manometer is used to measure
Atmospheric pressure
Pressure in pipes and channels
Pressure in Venturimeter
Difference of pressures between two points in a pipe
Unit of surface tension is
Energy/unit area
Velocity/unit area
Both of the above
It has no units
Viscous force is the __________ of shear stress due to viscosity and cross-section area of flow.
Sum
Different
Product
Ratio
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 intensity of pressure at any point, in a liquid, is
Directly proportional to the area of the vessel containing liquid
Directly proportional to the depth of liquid from the surface
Directly proportional to the length of the vessel containing liquid
Inversely proportional to the depth of liquid from the surface
One poise is equal to
0.1 N-s/m2
1 N-s/m2
10 N-s/m2
100 N-s/m2
The discharge through a large rectangular orifice is given by (where H1 = Height of the liquid above the top of the orifice, H2 = Height of the liquid above the bottom of the orifice, b = Breadth of the orifice, and Cd = Coefficient of discharge)
Q = (2/3) Cd × b × √(2g) × (H2 - H1)
Q = (2/3) Cd × b × √(2g) × (H2 1/2 - H1 1/2)
Q = (2/3) Cd × b × √(2g) × (H2 3/2 - H1 3/2)
Q = (2/3) Cd × b × √(2g) × (H2 2 - H1 2)
Dynamic viscosity of most of the gases with rise in temperature
Increases
Decreases
Remain unaffected
Unpredictable
The line of action of the buoyant force acts through the Centroid of the
Submerged body
Volume of the floating body
Volume of the fluid vertically above the body
Displaced volume of the fluid
Froude 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 is called hyper-sonic, if the Mach number is
Less than unity
Unity
Between 1 and 6
None of these
The property by virtue of which a liquid opposes relative motion between its different layers is called
Surface tension
Coefficient of viscosity
Viscosity
Osmosis
For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
Cavitation will begin when
The pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid
Pressure becomes more than critical pressure
Flow is increased
Pressure is increased
Select the correct statement
Weber's number is the ratio of inertia force to elastic force.
Weber's number is the ratio of gravity force to surface tension force.
Weber's number is the ratio of viscous force to pressure force.
Weber's number is the ratio of inertia force to surface tension force.
The pressure at a point in a fluid will not be same in all the directions when the fluid is
Moving
Viscous
Viscous and static
Viscous and moving
Surface tension has the units of
Newton-sec/m
Newton-m/sec
Newton/m
Newton
A vertical wall is subjected to a pressure due to one kind of liquid, on one of its sides. The total pressure on the wall acts at a distance __________ from the liquid surface.
H/3
H/2
2H/3
3H/4
The value of coefficient of discharge is __________ the value of coefficient of velocity.
Less than
Same as
More than
None of these
The force present in a moving liquid is
Inertia force
Viscous force
Gravity force
All of these
Specific weight of water in S.I. units is equal to
1000 N/m3
10000 N/m3
9.81 × 103 N/m3
9.81 × 10⁶ N/m3
The discharge over a triangular notch is
Inversely proportional to H3/2
Directly proportional to H3/2
Inversely proportional to H5/2
Directly proportional to H5/2
Re-entrant or Borda's mouthpiece is an __________ mouthpiece.
Internal
External
Both A and B
None of these
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 hydraulic mean depth for a circular pipe of diameter (d) is
d/6
d/4
d/2
d
Property of a fluid by which its own molecules are attracted is called
Adhesion
Cohesion
Viscosity
Compressibility
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