The discharge through a channel of circular section will be maximum when the depth of water is __________ the diameter of the circular channel.
0.34 times
0.67 times
0.81 times
0.95 times
Correct Answer :
D. 0.95 times
Related Questions
During the opening of a valve in a pipe line, the flow is
Steady
Unsteady
Uniform
Laminar
A pipe of length more than double the diameter of orifice fitted externally or internally to the orifice is called a
Notch
Weir
Mouthpiece
Nozzle
The velocity of the liquid flowing through the divergent portion of a Venturimeter
Remains constant
Increases
Decreases
Depends upon mass of liquid
If mercury in a barometer is replaced by water, the height of 3.75 cm of mercury will be following cm of water
51 cm
50 cm
52 cm
52.2 cm
Unit of surface tension is
Energy/unit area
Velocity/unit area
Both of the above
It has no units
True one-dimensional 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
The magnitude and direction of the velocity do not change from point to point in the fluid
The fluid particles move in plane or parallel planes and the streamline patterns are identical in each plane
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
A venturi-flume is used to measure
Pressure of liquid
Discharge of liquid
Pressure difference between two points in a channel
Pressure difference between two points in a pipe
The rise or depression of liquid in a tube due to surface tension will increase in size of tube will
Increase
Remain unaffected
May increase or decrease depending on the characteristics of liquid
Decrease
The absolute pressure is equal to
Gauge pressure + atmospheric pressure
Gauge pressure - atmospheric pressure
Atmospheric pressure - gauge pressure
Gauge pressure - vacuum pressure
The loss of head at exit of a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
The liquid used in manometers should have
Low density
High density
Low surface tension
High surface tension
If the surface of liquid is convex, men
Cohesion pressure is negligible
Cohesion pressure is decreased
Cohesion pressure is increased
There is no cohesion pressure
The pressure in Pascals at a depth of 1 m below the free surface of a body of water will be equal to
1 Pa
91 Pa
981 Pa
9810 Pa
The siphon will work satisfactorily, if the minimum pressure in the pipe is __________ vapour pressure of liquid.
Equal to
Less than
More than
None of these
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 velocity at which the flow changes from laminar flow to turbulent flow is called
Critical velocity
Velocity of approach
Sub-sonic velocity
Super-sonic velocity
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
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
In a static fluid
Resistance to shear stress is small
Fluid pressure is zero
Linear deformation is small
Only normal stresses can exist
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 large Reynold number is indication of
Smooth and streamline flow
Laminar flow
Steady flow
Highly turbulent flow
In an internal mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to height of the liquid above the vena contracta.
Less than
More than
Equal to
None of these
The pressure of the liquid flowing through the divergent portion of a Venturimeter
Remains constant
Increases
Decreases
Depends upon mass of liquid
For hypersonic flow, the Mach number is
Unity
Greater than unity
Greater than 2
Greater than 4
Flow occurring in a pipeline when a valve is being opened is
Steady
Unsteady
Laminar
Vortex
Buoyant force is
Resultant force acting on a floating body
Equal to the volume of liquid displaced
Force necessary to keep a body in equilibrium
The resultant force on a body due to the fluid surrounding it
Mach number is significant in
Supersonics, as with projectiles and jet propulsion
Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.
Simultaneous motion through two fluids where there is a surface of discontinuity, gravity force, and wave making effects, as with ship's hulls
All of the above
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
The magnitude and direction of the velocity do not change from point to point in the fluid
The fluid particles move in plane or parallel planes and the streamline patterns are identical in each pleasure
The tangential velocity of the water element having a free vortex is
Directly proportional to its distance from the centre
Inversely proportional to its distance from the centre
Directly proportional to its (distance)2 from the centre
Inversely proportional to its (distance)2 from the centre