When a liquid is flowing through a pipe, the velocity of the liquid is
Maximum at the centre and minimum near the walls
Minimum at the centre and maximum near the walls
Zero at the centre and maximum near the walls
Maximum at the centre and zero near the walls
Correct Answer :
A. Maximum at the centre and minimum near the walls
Related Questions
The meatcentric height of a ship is 0.6 m and the radius of gyration is 4 m. The time of rolling of a ship is
4.1 s
5.2 s
10.4 s
14.1 s
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
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
The viscosity of a liquid __________ its rate of flow through a hole in a vessel.
Effects
Does not effect
Both A and B
None of these
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
A weir is said to be narrow-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
In a short cylindrical external mouthpiece, the vena contracta occurs at a distance __________ the diameter of the orifice from the outlet of orifice.
Equal to
One-fourth
One-third
One-half
An internal mouthpiece is said to be running free if the length of the mouthpiece is __________ the diameter of the orifice.
Less than twice
More than twice
Less than three times
More than three times
The pressure measured with the help of a pressure gauge is called
Atmospheric pressure
Gauge pressure
Absolute pressure
Mean pressure
The variation in the volume of a liquid with the variation of pressure is called its
Surface tension
Compressibility
Capillarity
Viscosity
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
A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction of it volume is under mercury?
The metal piece will simply float over the mercury
The metal piece will be immersed in mercury by half
Whole of the metal piece will be immersed with its top surface just at mercury level
Metal piece will sink to the bottom
The depth of the centre of pressure on a vertical rectangular gate 8 m wide and 6 m high, when the water surface coincides with the top of the gate, is
2.4 m
3.0 m
4.0 m
5.0 m
Rotameter is a device used to measure
Absolute pressure
Velocity of fluid
Flow
Rotation
A flow through a long pipe at constant rate is called
Steady uniform flow
Steady non-uniform flow
Unsteady uniform flow
Unsteady non-uniform flow
For a perfect incompressible liquid, flowing in a continuous stream, the total energy of a particle remains the same, while the particle moves from one point to another. This statement is called
Continuity equation
Bernoulli's equation
Pascal's law
Archimedess principle
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
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
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
According to Bernoulli's equation
Z + p/w + v²/2g = constant
Z + p/w - v²/2g = constant
Z - p/w + v²/2g = constant
Z - p/w - v²/2g = constant
According to the principle of buoyancy a body totally or partially immersed in a fluid will be lifted up by a force equal to
The weight of the body
More than the weight of the body
Less than the weight of the body
Weight of the fluid displaced by the body
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
In case of flow through parallel pipes,
The head loss for all the pipes is same
The total discharge is equal to the sum of discharges in the various pipes
The total head loss is the sum of head losses in the various pipes
Both (A) and (B)
Gauge pressure at a point is equal to the absolute pressure __________ the atmospheric pressure.
Plus
Minus
Divide
Multiply
According to Francis formula, the discharge over a rectangular weir is (where n = Number of end contractions)
(2/3) × Cd (L - nH) × √(2gh)
(2/3) × Cd (L - 0.1nH) × √(2g) × H3/2
(2/3) × Cd (L - nH) × √(2g) × H²
(2/3) × Cd (L - nH) × √(2g) × H5/2
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
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
An orifice is said to be large, if
The size of orifice is large
The velocity of flow is large
The available head of liquid is more than 5 times the height of orifice
The available head of liquid is less than 5 times the height of orifice
Metacentric height is given as the distance between
The center of gravity of the body and the metacentre
The center of gravity of the body and the center of buoyancy
The center of gravity of the body and the center of pressure
Center of buoyancy and metacentre
Euler's equation in the differential form for the motion of liquids is given by
dp/ρ + g.dz + v.dv = 0
dp/ρ - g.dz + v.dv = 0
ρ.dp + g.dz + v.dv = 0
ρ.dp - g.dz + v.dv = 0