The surface tension of mercury at normal temperature compared to that of water is
More
Less
Same
More or less depending on size of glass tube
Correct Answer :
A. More
Related Questions
The two important forces for a floating body are
Buoyancy, gravity
Buoyancy, pressure
Buoyancy, inertial
Inertial, gravity
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
Metacentre is the point of intersection of
Vertical upward force through e.g. of body and center line of body
Buoyant force and the center line of body
Midpoint between e.g. and center of buoyancy
All of the above
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
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 flow in which each liquid particle has a definite path and their paths do not cross each other is called
One dimensional flow
Streamline flow
Steady flow
Turbulent flow
The diameter of the nozzle (d) for maximum transmission of power is given by (where D = Diameter of pipe, f = Darcys coefficient of friction for pipe, and l = Length of pipe)
d = (D⁵/8fl)1/2
d = (D⁵/8fl)1/3
d = (D⁵/8fl)1/4
d = (D⁵/8fl)1/5
The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v = Velocity of the liquid in the pipe, μ = Viscosity of the liquid, and w = Specific weight of the flowing liquid)
4μvl/wd²
8μvl/wd²
16μvl/wd²
32μvl/wd²
According to Manning's formula, the discharge through an open channel is (where M = Manning's constant)
A × M × m1/2 × i2/3
A × M × m2/3 × i1/2
A1/2 × M2/3 × m × i
A2/3 × M1/3 × m × i
The point at which the resultant pressure on an immersed surface acts, is known as
Centre of gravity
Centre of depth
Centre of pressure
Centre of immersed surface
The velocity at which the laminar flow stops, is known as
Velocity of approach
Lower critical velocity
Higher critical velocity
None of these
In a footstep bearing, if the radius of the shaft is doubled, then the torque required to overcome the viscous resistance will be
Double
Four times
Eight times
Sixteen times
The hydraulic mean depth or the hydraulic radius is the ratio of
Area of flow and wetted perimeter
Wetted perimeter and diameter of pipe
Velocity of flow and area of flow
None of these
One stoke is equal to
10-2 m2/s
10-3 m2/s
10-4 m2/s
10-6 m2/s
The center of gravity of the volume of the liquid displaced by an immersed body is called
Metacentre
Center of pressure
Center of buoyancy
Center of gravity
When a cylindrical vessel containing liquid is revolved about its vertical axis at a constant angular velocity, the pressure
Varies as the square of the radial distance
Increases linearly as its radial distance
Increases as the square of the radial distance
Decreases as the square of the radial distance
Center of pressure compared to e.g. is
Above it
Below it
At same point
Above or below depending on area of body
A nozzle placed at the end of a water pipe line discharges water at a
Low pressure
High pressure
Low velocity
High velocity
The tendency of a liquid surface to contract is due to the following property
Cohesion
Adhesion
Viscosity
Surface tension
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 critical depth meter is used to measure
Velocity of flow in an open channel
Depth of flow in an open channel
Hydraulic jump
Depth of channel
The sheet of water flowing over a notch or a weir is known as
Sill or crest
Nappe or vein
Orifice
None of these
The total energy line lies over the hydraulic gradient line by an amount equal to the
Pressure head
Velocity head
Pressure head + velocity head
Pressure head - velocity head
Bernoulli equation deals with the law of conservation of
Mass
Momentum
Energy
Work
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
The loss of head at entrance in a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
The top of the weir over which the water flows is known as
Sill or crest
Nappe or vein
Orifice
None of these
Which of the following is an example of laminar flow?
Underground flow
Flow past tiny bodies
Flow of oil in measuring instruments
All of these
The line of action of the buoyant force acts through the
Centroid of the volume of fluid vertically above the body
Centre of the volume of floating body
Center of gravity of any submerged body
Centroid of the displaced volume of fluid
A nozzle is generally made of
Cylindrical shape
Convergent shape
Divergent shape
Convergent-divergent shape