For pipes, turbulent flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
Correct Answer :
C. More than 4000
Related Questions
An open vessel of water is accelerated up an inclined plane. The free water surface will
Be horizontal
Make an angle in direction of inclination of inclined plane
Make an angle in opposite direction to inclination of inclined plane
Any one of above is possible
The coefficient of discharge for an external mouthpiece depends upon
Velocity of liquid
Pressure of liquid
Area of mouthpiece
Length of mouthpiece
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
An ideal flow of any fluid must fulfil the following
Newton's law of motion
Newton's law of viscosity
Pascal' law
Continuity equation
In a venturi-flume, the flow takes place at
Atmospheric pressure
Gauge pressure
Absolute pressure
None of these
A pressure of 25 m of head of water is equal to
25 kN/ m²
245 kN/ m²
2500 kN/m²
2.5 kN/ m²
Choose the wrong statement
Any weight, floating or immersed in a liquid, is acted upon by a buoyant force
Buoyant force is equal to the weight of the liquid displaced
The point through which buoyant force acts, is called the center of buoyancy
Center of buoyancy is located above the center of gravity of the displaced liquid
The total energy of each particle at various places in the case of perfect incompressible fluid flowing in continuous stream
Keeps on increasing
Keeps on decreasing
Remain constant
May increase/decrease
Bernoulli's equation is applied to
Venturimeter
Orifice meter
Pitot tube
All of these
If the depth of water in an open channel is less than the critical depth, the flow is called
Critical flow
Turbulent flow
Tranquil flow
Torrential flow
Differential manometer is used to measure
Pressure in pipes, channels etc.
Atmospheric pressure
Very low pressure
Difference of pressure between two points
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
The centre of gravity of the volume of the liquid displaced is called
Centre of pressure
Centre of buoyancy
Metacentre
None of these
In an isothermal atmosphere, the pressure
Decreases linearly with elevation
Remain constant
Varies in the same way as the density
Increases exponentially with elevation
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
A body floats in stable equilibrium
When its meatcentric height is zero
When the metacentre is above C.G.
When its e.g. is below its center of buoyancy
Metacentre has nothing to do with position of e.g. for determining stability
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
A model of torpedo is tested in a towing tank at a velocity of 25 m/sec. The prototype is expected to attain a velocity of 5 m/sec. What model scale has been used?
1 : 5
1 : 2.5
1 : 25
1 : √5
The ratio of specific weight of a liquid to the specific weight of pure water at a standard temperature is called
Density of liquid
Specific gravity of liquid
Compressibility of liquid
Surface tension of liquid
The force of buoyancy is always __________ the weight of the liquid displaced by the body.
Equal to
Less than
More than
None of these
The discharge over a right angled notch is (where H = Height of liquid above the apex of notch)
(8/15) Cd. 2g. H
(8/15) Cd. 2g. H3/2
(8/15) Cd. 2g. H²
(8/15) Cd. 2g. H5/2
A fluid in equilibrium can't sustain
Tensile stress
Compressive stress
Shear stress
Bending stress
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
When the Venturimeter is inclined, then for a given flow it will show __________ reading.
Same
More
Less
None of these
The most efficient section of a channel is
Triangular
Rectangular
Square
Trapezoidal
The weight per unit volume of a liquid at a standard temperature and pressure is called
Specific weight
Mass density
Specific gravity
None of these
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
Uniform flow occurs when
The flow is steady
The flow is streamline
Size and shape of the cross section in a particular length remain constant
Size and cross section change uniformly along length
The length AB of a pipe ABC in which the liquid is flowing has diameter (d1) and is suddenly enlarged to diameter (d2) at B which is constant for the length BC. The loss of head due to sudden enlargement is
(v₁ - v₂)²/g
(v₁² - v₂²)/g
(v₁ - v₂)²/2g
(v₁² - v₂²)/2g
If w is the specific weight of liquid and k the depth of any point from the surface, then pressure intensity at that point will be
h
wh
w/h
h/w