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
Correct Answer :
B. (2/3) × Cd (L - 0.1nH) × √(2g) × H3/2
Related Questions
A structure, whose width is __________ the width of the channel, is called a flumed structure.
Less than
More than
Equal
None of these
The factional resistance of a pipe varies approximately with __________ of the liquid.
Pressure
Velocity
Square of velocity
Cube of velocity
The discharge through an external mouthpiece is given by (where a = Cross-sectional area of the mouthpiece, and H = Height of liquid above the mouthpiece)
0.855 a.√(2gH)
1.855 aH.√(2g)
1.585 a.√(2gH)
5.85 aH.√(2g)
The theoretical velocity of jet at vena contracta is (where H = Head of water at vena contracta)
2gH
H × √(2g)
2g × √H
√(2gh)
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
In a footstep bearing, if the radius of the shaft is doubled, then the torque required to overcome the viscous resistance will be
Double
Four times
Eight times
Sixteen times
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
Fluid is a substance which offers no resistance to change of
Pressure
Flow
Shape
Volume
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
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
Surface tension
Acts in the plane of the interface normal to any line in the surface
Is also known as capillarity
Is a function of the curvature of the interface
Decreases with fall in temperature
Bernoulli equation deals with the law of conservation of
Mass
Momentum
Energy
Work
The power transmitted through the pipe is maximum when the head lost due to friction is equal to
One-fourth of the total supply head
One-third of the total supply head
One-half of the total supply head
Two-third of the total supply head
Hot wire anemometer is used to measure
Pressure in gases
Liquid discharge
Pressure in liquids
Gas velocities
The angle of contact in case of a liquid depends upon
The nature of the liquid and the solid
The material which exists above the free surface of the liquid
Both of die above
Any one of the above
The coefficient of discharge for an external mouthpiece depends upon
Velocity of liquid
Pressure of liquid
Area of mouthpiece
Length of mouthpiece
The power transmitted through a pipe is (where w = Specific weight in N/m3, and Q = Discharge in m3/s)
w × Q × H
w × Q × hf
w × Q (H - hf)
w × Q (H + hf)
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 capillary rise at 20°C in a clean glass tube of 1 mm bore containing water is approximately
5 mm
10 mm
20 mm
30 mm
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
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
The most economical section of a rectangular channel is one which has hydraulic mean depth or hydraulic radius equal to
Half the depth
Half the breadth
Twice the depth
Twice the breadth
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
The intensity of pressure at any point, in a liquid, is __________ to the depth of liquid from the surface.
Equal
Directly proportional
Inversely proportional
None of these
For a floating body to be in stable equilibrium, its metacentre should be
Below the center of gravity
Below the center of buoyancy
Above the center of buoyancy
Above the center of gravity
The stability of a dam is checked for
Tension at the base
Overturning of the wall or dam
Sliding of the wall or dam
All of these
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a triangular notch is given by
dQ/Q = 3/2 × (dH/H)
dQ/Q = 2 × (dH/H)
dQ/Q = 5/2 × (dH/H)
dQ/Q = 3 × (dH/H)
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
The meatcentric height is the distance between the
Centre of gravity of the floating body and the centre of buoyancy
Centre of gravity of the floating body and the metacentre
Metacentre and centre of buoyancy
Original centre of buoyancy and new centre of buoyancy
The flow in a pipe is neither laminar nor turbulent when Reynold number is
Less than 2000
Between 2000 and 2800
More than 2800
None of these