The total pressure on the top of a closed cylindrical vessel of radius (r) completely filled up with liquid of specific weight (w) and rotating at (ω) rad/s about its vertical axis, is
π w ω² r²/4g
π w ω² r³/4g
π w ω² r⁴/4g
π w ω² r²/2g
Correct Answer :
C. π w ω² r⁴/4g
Related Questions
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
When the water level on the downstream side of a weir is above the top surface of a weir, the weir is known as
Narrow-crested weir
Broad-crested weir
Ogee weir
Submerged weir
The density of water is 1000 kg/m3 at
0° C
0° K
4° C
20° C
Liquids
Cannot be compressed
Occupy definite volume
Are not affected by change in pressure and temperature
None of the above
Poise is the unit of
Surface tension
Capillarity
Viscosity
Shear stress in fluids
In a lock-gate, the reaction between two gates is (where P = Resultant pressure on the lock gate, and α = Inclination of the gate with the normal to the side of the lock)
p/sinα
2p/sinα
p/2sinα
2p/sin (α/2)
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
Dynamic viscosity of most of the liquids with rise in temperature
Increases
Decreases
Remain unaffected
Unpredictable
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
A flow is called sub-sonic, if the Mach number is
Less than unity
Unity
Between 1 and 6
More than 6
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
A Piezometer tube is used only for measuring
Low pressure
High pressure
Moderate pressure
Vacuum pressure
A weir is said to be broad 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
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
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 total head of a liquid particle in motion is equal to
Pressure head + kinetic head + potential head
Pressure head - (kinetic head + potential head)
Potential head - (pressure head + kinetic head)
Kinetic head - (pressure head + potential head)
The loss of pressure head in case of laminar flow is proportional to
Velocity
(Velocity)2
(Velocity)3
(Velocity)4
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 resultant upward pressure of a fluid on a floating body is equal to the weight of the fluid displaced by the body. This definition is according to
Buoyancy
Equilibrium of a floating body
Archimedes' principle
Bernoulli's theorem
In open channels, the specific energy is the
Total energy per unit discharge
Total energy measured with respect to the datum passing through the bottom of the channel
Total energy measured above the horizontal datum
Kinetic energy plotted above the free surface of water
When a body is placed over a liquid, it will sink down if
Gravitational force is equal to the up-thrust of the liquid
Gravitational force is less than the up-thrust of the liquid
Gravitational force is more than the up-thrust of the liquid
None of the above
The body will float if the force of buoyancy is __________ the weight of the liquid displaced.
Equal to
Less than
More than
None 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
Coefficient of velocity is defined as the ratio of
Actual velocity of jet at vena contracta to the theoretical velocity
Area of jet at vena contracta to the area of orifice
Actual discharge through an orifice to the theoretical discharge
None of the above
The buoyancy depends upon the
Weight of the liquid displaced
Pressure with which the liquid is displaced
Viscosity of the liquid
Compressibility of the liquid
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
The total pressure on an immersed surface inclined at an angle θ with the liquid surface is
wA
wx
wAx
wAx/sinθ
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
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
A compound pipe of diameter d1, d2 and d3 having lengths l1, l2 and l3 is to be replaced by an equivalent pipe of uniform diameter d and of the same length (l) as that of the compound pipe. The size of the equivalent pipe is given by
l/d² = (l₁/d₁²) + (l₂/d₂²) + (l₃/d₃²)
l/d³ = (l₁/d₁³) + (l₂/d₂³) + (l₃/d₃³)
l/d⁴ = (l₁/d₁⁴) + (l₂/d₂⁴) + (l₃/d₃⁴)
l/d⁵ = (l₁/d₁⁵) + (l₂/d₂⁵) + (l₃/d₃⁵)