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
Correct Answer :
C. (v₁ - v₂)²/2g
Related Questions
When a vertical wall is subjected to pressures due to liquid on both sides, the resultant pressure is the __________ of the two pressures.
Sum
Difference
Arithmetic mean
Geometric mean
For a floating body to be in equilibrium
Meta centre should be above e.g.
Centre of buoyancy and e.g. must lie on same vertical plane
A righting couple should be formed
All of the above
For similarity, in addition to models being geometrically similar to prototype, the following in both cases should also be equal
Ratio of inertial force to force due to viscosity
Ratio of inertial force to force due to gravitation
Ratio of inertial force to force due to surface tension
All the four ratios of inertial force to force due to viscosity, gravitation, surface tension, and elasticity
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
Pressure of the order of 10 torr can be measured by
Bourdon tube
Pirani Gauge
Micro-manometer
Lonisation gauge
A structure, whose width is __________ the width of the channel, is called a flumed structure.
Less than
More than
Equal
None of these
The difference of pressure between the inside and outside of a liquid drop is
p = T × r
p = T/r
p = T/2r
p = 2T/r
The surface tension of mercury at normal temperature is __________ that of water.
Same as
Lower than
Higher than
None of these
Barometer is used to measure
Pressure in pipes, channels etc.
Atmospheric pressure
Very low pressure
Difference of pressure between two points
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
A piece of wood having weight 5 kg floats in water with 60% of its volume under the liquid. The specific gravity of wood is
0.83
0.6
0.4
0.3
The dynamic viscosity of the liquid __________ with rise in temperature.
Remain unaffected
Increases
Decreases
None of these
A metal with specific gravity of a floating in a fluid of same specific gravity a will
Sink to bottom
Float over fluid
Partly immersed
Be fully immersed with top surface at fluid surface
According to Chezy's formula, the discharge through an open channel is (where A = Area of flow, C = Chezy's constant, m = Hydraulic mean depth, and i = Uniform slope in bed)
A × √(m × i)
C × √(m × i)
AC × √(m × i)
mi × √(A × C)
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 velocity corresponding to Reynold number of 2000 is called
Sub-sonic velocity
Super-sonic velocity
Lower critical velocity
Higher critical velocity
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
In order that flow takes place between two points in a pipeline, the differential pressure between these points must be more than
Frictional force
Viscosity
Surface friction
All of the above
The flow in a pipe or channel is said to be uniform when
The liquid particles at all sections have the same velocities
The liquid particles at different sections have different velocities
The quantity of liquid flowing per second is constant
Each liquid particle has a definite path
The total pressure on the top of a closed cylindrical vessel completely filled up with a liquid is
Directly proportional to (radius)2
Inversely proportional to (radius)2
Directly proportional to (radius)4
Inversely proportional to (radius)4
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 absolute pressure is equal to
Gauge pressure + atmospheric pressure
Gauge pressure - atmospheric pressure
Atmospheric pressure - gauge pressure
Gauge pressure - vacuum pressure
The force exerted by a moving fluid on an immersed body is directly proportional to the rate of change of momentum due to the presence of the body. This statement is called
Newton's law of motion
Newton's law of cooling
Newton's law of viscosity
Newton's law of resistance
A streamline is defined as the line
Parallel to central axis flow
Parallel to outer surface of pipe
Of equal velocity in a flow
Along which the pressure drop is uniform
The mercury does not wet the glass. This is due to the property of the liquid known as
Cohesion
Adhesion
Viscosity
Surface tension
The increase in pressure at the outer edge of a drum of radius (r) completely filled up with liquid of density (ρ) and rotating at (ω) rad/s is
ρ ω2 r2
2ρ ω2 r2
ρ ω2 r2/2
ρ ω2 r2/4
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
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 most efficient section of a channel is
Triangular
Rectangular
Square
Trapezoidal
The unit of kinematic viscosity in S. I. units is
N-m/s
N-s/m2
m2/s
N-m