The most efficient section of a channel is
Triangular
Rectangular
Square
Trapezoidal
Correct Answer :
D. Trapezoidal
Related Questions
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)
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
The velocity of jet of water travelling out of opening in a tank filled with water is proportional to
Head of water (h)
h²
V/T
h/2
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
A channel is said to be of most economical cross-section, if
It gives maximum discharge for a given cross-sectional area and bed slope
It has minimum wetted perimeter
It involves lesser excavation for the designed amount of discharge
All of the above
Fluid is a substance which offers no resistance to change of
Pressure
Flow
Shape
Volume
The pressure of the liquid flowing through the divergent portion of a Venturimeter
Remains constant
Increases
Decreases
Depends upon mass of liquid
Specific weight of sea water is more that of pure water because it contains
Dissolved air
Dissolved salt
Suspended matter
All of the above
Coefficient of contraction is the ratio of
Actual velocity of jet at vena contracta to the theoretical velocity
Loss of head in the orifice to the head of water available at the exit of the orifice
Loss of head in the orifice to the head of water available at the exit of the orifice
Area of jet at vena-contracta to the area of orifice
When a cylindrical vessel containing liquid is resolved, the surface of the liquid takes the shape of
A triangle
A paraboloid
An ellipse
None of these
When a plate is immersed in a liquid parallel to the flow, it will be subjected to a pressure __________ that if the same plate is immersed perpendicular to the flow.
Less than
More than
Equal to
None of these
The discharge of a depressed nappe is 6 to 7 percent __________ that of a free nappe.
Less than
More than
Equal to
None of these
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
The velocity at which the laminar flow stops, is known as
Velocity of approach
Lower critical velocity
Higher critical velocity
None of these
Metacentre is the point of intersection of
Vertical upward force through e.g. of body and center line of body
Buoyant force and the center line of body
Midpoint between e.g. and center of buoyancy
All of the above
A pitot tube is used to measure the
Velocity of flow at the required point in a pipe
Pressure difference between two points in a pipe
Total pressure of liquid flowing in a pipe
Discharge through a pipe
The kinematic viscosity is the
Ratio of absolute viscosity to the density of the liquid
Ratio of density of the liquid to the absolute viscosity
Product of absolute viscosity and density of the liquid
Product of absolute viscosity and mass of the liquid
In the case of steady flow of a fluid, the acceleration of any fluid particle is
Constant
Variable
Zero
Zero under limiting conditions
According to equation of continuity,
w1a1 = w2a2
w1v1 = w2v2
a1v1 = a2v2
a1/v1 = a2/v2
The rise of liquid along the walls of a revolving cylinder about the initial level is __________ the depression of the liquid at the axis of rotation.
Same as
Less than
More than
None of these
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 loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number)
1/RN
4/RN
16/RN
64/RN
For pipes, laminar flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
Water is __________ liquid.
A compressible
An incompressible
Both A and B
None of these
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
Falling drops of water become spheres due to the property of
Adhesion
Cohesion
Surface tension
Viscosity
If the coefficient of discharge is 0.6, then the discharge over a right angled notch is
0.417 H5/2
1.417 H5/2
4.171 H5/2
7.141 H5/2
When the flow parameters at any given instant remain same at every point, then flow is said to be
Quasi-static
Steady state
Laminar
Uniform
The critical depth for a channel is given by (where q = Unit discharge (discharge per unit width) through the channel)
(q/g)1/2
(q²/g)1/3
(q³/g)1/4
(q⁴/g)1/5
One cubic metre of water weighs
100 litres
250 litres
500 litres
1000 litres