For pipes, laminar flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
Correct Answer :
A. Less than 2000
Related Questions
Which of the following manometer has highest sensitivity?
U-tube with water
Inclined U-tube
U-tube with mercury
Micro-manometer with water
Piezometer is used to measure
Pressure in pipe, channels etc.
Atmospheric pressure
Very low pressures
Difference of pressure between two points
The flow in which the particles of a fluid attain such velocities that varies from point to point in magnitude and direction as well as from instant to instant, is known as
One dimensional flow
Uniform flow
Steady flow
Turbulent flow
The magnitude of water hammer depends upon the
Elastic properties of the pipe material
Elastic properties of the liquid flowing through the pipe
Speed at which the valve is closed
All of the above
Bulk modulus of a fluid is the ratio of
Shear stress to shear strain
Increase in volume to the viscosity of fluid
Increase in pressure to the volumetric strain
Critical velocity to the viscosity of fluid
A fluid which obeys the Newton's law of viscosity is termed as
Real fluid
Ideal fluid
Newtonian fluid
Non-Newtonian fluid
The resultant upward pressure of the fluid on an immersed body due to its tendency to uplift the submerged body is called
Up-thrust
Reaction
Buoyancy
Metacentre
The total pressure on an immersed surface inclined at an angle θ with the liquid surface is
wA
wx
wAx
wAx/sinθ
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
Newton's law of viscosity is a relationship between
Shear stress and the rate of angular distortion
Shear stress and viscosity
Shear stress, velocity and viscosity
Pressure, velocity and viscosity
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
A thick liquid like syrup has a __________ viscosity than a light liquid like water.
Lesser
Greater
Same
None of these
The force present in a moving liquid is
Inertia force
Viscous force
Gravity force
All of these
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a rectangular notch is given by
dQ/Q = (1/2) × (dH/H)
dQ/Q = (3/4) × (dH/H)
dQ/Q = (dH/H)
dQ/Q = (3/2) × (dH/H)
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
The tendency of a liquid surface to contract is due to the following property
Cohesion
Adhesion
Viscosity
Surface tension
The top of the weir over which the water flows is known as
Sill or crest
Nappe or vein
Orifice
None of these
A structure, whose width is __________ the width of the channel, is called a flumed structure.
Less than
More than
Equal
None of these
A tank of uniform cross-sectional area (A) containing liquid upto height (H1) has an orifice of cross-sectional area (a) at its bottom. The time required to empty the tank completely will be
(2A√H₁)/(Cd × a√2g)
(2AH₁)/(Cd × a√2g)
(2AH₁3/2)/(Cd × a√2g)
(2AH₁²)/(Cd × a√2g)
Two pipe systems can be said to be equivalent, when the following quantities are same
Friction loss and flow
Length and diameter
Flow and length
Friction factor and diameter
Alcohol is used in manometers because
It has low vapour pressure
It is clearly visible
It has low surface tension
It can provide longer column due to low density
Center of pressure compared to e.g. is
Above it
Below it
At same point
Above or below depending on area of body
Flow occurring in a pipeline when a valve is being opened is
Steady
Unsteady
Laminar
Vortex
When a cylindrical vessel, containing some liquid, is rotated about its vertical axis, the liquid surface is depressed down at the axis of its rotation and rises up near the walls of the vessel on all sides. This type of flow is known as
Steady flow
Turbulent flow
Vortex flow
Uniform flow
The normal stress is same in all directions at a point in a fluid
Only when the fluid is frictionless
Only when the fluid is incompressible and has zero viscosity
When there is no motion of one fluid layer relative to an adjacent layer
Irrespective of the motion of one fluid layer relative to an adjacent layer
In a broad-crested weir, the discharge is maximum if the head of water on the downstream side of weir is __________ the head of water on the upstream side of weir.
Equal to
One-third
Two-third
Three-fourth
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
Water is __________ liquid.
A compressible
An incompressible
Both A and B
None of these
Newton's law of viscosity is a relationship between
Pressure, velocity and temperature
Shear stress and rate of shear strain
Shear stress and velocity
Rate of shear strain and temperature