Free surface of a liquid behaves like a sheet and tends to contract to smallest possible area due to the
Force of adhesion
Force of cohesion
Force of friction
Force of diffusion
Correct Answer :
B. Force of cohesion
Related Questions
A balloon lifting in air follows the following principle
Law of gravitation
Archimedes principle
Principle of buoyancy
All of the above
The value of coefficient of discharge is __________ the value of coefficient of velocity.
Less than
Same as
More than
None of these
Whenever a plate is held immersed at some angle with the direction of flow of the liquid, it is subjected to some pressure. The component of this pressure, in the direction of flow of the liquid, is known as
Lift
Drag
Stagnation pressure
Bulk modulus
A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specific gravity is
1
5
7
6
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 power absorbed (in watts) in overcoming the viscous resistance of a footstep bearing is
μ π³ N² R² /1800 t
μ π³ N² R⁴ /1800 t
μ π³ N² R² /3600 t
μ π³ N² R⁴ /3600 t
According to Manning's formula, the discharge through an open channel is (where M = Manning's constant)
A × M × m1/2 × i2/3
A × M × m2/3 × i1/2
A1/2 × M2/3 × m × i
A2/3 × M1/3 × m × i
Ratio of inertia force to surface Jension is known as
Mach number
Froude number
Reynoldss number
Weber's number
The continuity equation is connected with
Open channel/pipe flow
Compressibility of fluids
Conservation of mass
Steady/unsteady flow
Which of the following statement is wrong?
A flow whose streamline is represented by a curve is called two dimensional flow.
The total energy of a liquid particle is the sum of potential energy, kinetic energy and pressure energy.
The length of divergent portion in a Venturimeter is equal to the convergent portion.
A pitot tube is used to measure the velocity of flow at the required point in a pipe.
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
In a footstep bearing, if the speed of the shaft is doubled, then the torque required to overcome the viscous resistance will be
Double
Four times
Eight times
Sixteen times
The body will sink down if the force of buoyancy is __________ the weight of the liquid displaced.
Equal to
Less than
More than
None of these
The property of a liquid which offers resistance to the movement of one layer of liquid over another adjacent layer of liquid, is called
Surface tension
Compressibility
Capillarity
Viscosity
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
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
The loss of head at entrance in a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
Re-entrant or Borda's mouthpiece is an __________ mouthpiece.
Internal
External
Both A and B
None of these
The two important forces for a floating body are
Buoyancy, gravity
Buoyancy, pressure
Buoyancy, inertial
Inertial, gravity
In an external mouthpiece, the absolute pressure head at vena contracta is __________ the atmospheric pressure head by an amount equal to 0.89 times the height of the liquid, above the vena contracta.
Less than
More than
Equal to
None of these
A differential manometer is used to measure
Atmospheric pressure
Pressure in pipes and channels
Pressure in Venturimeter
Difference of pressures between two points in a pipe
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 discharge over a right angled notch is (where H = Height of liquid above the apex of notch)
(8/15) Cd. 2g. H
(8/15) Cd. 2g. H3/2
(8/15) Cd. 2g. H²
(8/15) Cd. 2g. H5/2
The unit of viscosity is
Metres² per sec
kg-sec/metre
Newton-sec per metre²
Newton-sec per meter
If cohesion between molecules of a fluid is greater than adhesion between fluid and glass, then the free level of fluid in a dipped glass tube will be
Higher than the surface of liquid
The same as the surface of liquid
Lower than the surface of liquid
Unpredictable
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
Ratio of inertia force to elastic force is known as
Mach number
Froude number
Reynolds number
Weber's number
An orifice is said to be large, if
The size of orifice is large
The velocity of flow is large
The available head of liquid is more than 5 times the height of orifice
The available head of liquid is less than 5 times the height of orifice
The length of a liquid stream while flowing over a weir __________ at the ends of the sill.
Expands
Does not change
Contracts
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