The coefficient of discharge for an external mouthpiece is
0.375
0.5
0.707
0.855
Correct Answer :
D. 0.855
Related Questions
Capillary action is due to the
Surface tension
Cohesion of the liquid
Adhesion of the liquid molecules and the molecules on the surface of a solid
All of the above
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
The units of kinematic viscosity are
Metres² per sec
kg sec/metre
Newton-sec per metre
Newton-sec per metre
Cavitation is caused by
High velocity
High pressure
Weak material
Low pressure
A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction of it volume is under mercury?
The metal piece will simply float over the mercury
The metal piece will be immersed in mercury by half
Whole of the metal piece will be immersed with its top surface just at mercury level
Metal piece will sink to the bottom
Dimensions of surface tension are
ML°T⁻²
ML°T
ML r²
ML²T²
The coefficient of discharge for an external mouthpiece is
0.375
0.5
0.707
0.855
The shear stress between the two liquid layers is __________ proportional to the distance between two layers.
Directly
Inversely
Both A and B
None of these
A vertical wall is subjected to a pressure due to one kind of liquid, on one of its sides. Which of the following statement is correct?
The pressure on the wall at the liquid level is minimum
The pressure on the bottom of the wall is maximum
The pressure on the wall at the liquid level is zero, and on the bottom of the wall is maximum
The pressure on the bottom of the wall is zer
The density of water is 1000 kg/m3 at
0° C
0° K
4° C
20° C
Choose the wrong statement
The horizontal component of the hydrostatic force on any surface is equal to the normal force on the vertical projection of the surface
The horizontal component acts through the center of pressure for the vertical projection
The vertical component of the hydrostatic force on any surface is equal to the weight of the volume of the liquid above the area
The vertical component passes through the center of pressure of the volume
For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
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
With an increase in size of tube, the rise or depression of liquid in the tube due to surface tension will
Decrease
Increase
Remain unchanged
Depend upon the characteristics of liquid
The discharge over a triangular notch is
Inversely proportional to H3/2
Directly proportional to H3/2
Inversely proportional to H5/2
Directly proportional to H5/2
Falling drops of water become spheres due to the property of
Adhesion
Cohesion
Surface tension
Viscosity
In a short cylindrical external mouthpiece, the vena contracta occurs at a distance __________ the diameter of the orifice from the outlet of orifice.
Equal to
One-fourth
One-third
One-half
The flow in a pipe or channel is said to be non-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 fluid whose viscosity does not change with the rate of deformation or shear strain is known as
Real fluid
Ideal fluid
Newtonian fluid
Non-Newtonian fluid
The mass of 2.5 m3 of a certain liquid is 2 tonnes. Its mass density is
200 kg/m3
400 kg/m3
600 kg/m3
800 kg/m3
Choose the wrong statement
Any weight, floating or immersed in a liquid, is acted upon by a buoyant force
Buoyant force is equal to the weight of the liquid displaced
The point through which buoyant force acts, is called the center of buoyancy
Center of buoyancy is located above the center of gravity of the displaced liquid
The diameter of the nozzle (d) for maximum transmission of power is given by (where D = Diameter of pipe, f = Darcys coefficient of friction for pipe, and l = Length of pipe)
d = (D⁵/8fl)1/2
d = (D⁵/8fl)1/3
d = (D⁵/8fl)1/4
d = (D⁵/8fl)1/5
Dynamic viscosity of most of the liquids with rise in temperature
Increases
Decreases
Remain unaffected
Unpredictable
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
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a rectangular notch is given by
dQ/Q = (1/2) × (dH/H)
dQ/Q = (3/4) × (dH/H)
dQ/Q = (dH/H)
dQ/Q = (3/2) × (dH/H)
The buoyancy depends upon the
Weight of the liquid displaced
Pressure with which the liquid is displaced
Viscosity of the liquid
Compressibility of the liquid
If a body floating in a liquid returns back to its original position, when given a small angular displacement, the body is said to be in
Neutral equilibrium
Stable equilibrium
Unstable equilibrium
None of these
The specific gravity of an oil whose specific weight is 7.85 kN/m3, is
0.8
1
1.2
1.6
The ratio of the inertia force to the __________ is called Euler's number.
Pressure force
Elastic force
Surface tension force
Viscous force
Euler's equation in the differential form for the motion of liquids is given by
dp/ρ + g.dz + v.dv = 0
dp/ρ - g.dz + v.dv = 0
ρ.dp + g.dz + v.dv = 0
ρ.dp - g.dz + v.dv = 0