The unit of surface tension is
N/m
N/m2
N/m3
N-m
Correct Answer :
A. N/m
Related Questions
Viscous force is the __________ of shear stress due to viscosity and cross-section area of flow.
Sum
Different
Product
Ratio
A one dimensional flow is one which
Is uniform flow
Is steady uniform flow
Takes place in straight lines
Involves zero transverse component of flow
The unit of kinematic viscosity in S. I. units is
N-m/s
N-s/m2
m2/s
N-m
Liquids
Cannot be compressed
Occupy definite volume
Are not affected by change in pressure and temperature
None of the above
Cavitation will begin when
The pressure at any location reaches an absolute pressure equal to the saturated vapour pressure of the liquid
Pressure becomes more than critical pressure
Flow is increased
Pressure is increased
The total energy line lies over the centre line of the pipe by an amount equal to
Pressure head
Velocity head
Pressure head + velocity head
Pressure head - velocity head
In a free vortex motion, the radial component of velocity everywhere is
Maximum
Minimum
Zero
Nonzero and finite
Total pressure on a lmxlm gate immersed vertically at a depth of 2 m below the free water surface will be
1000 kg
4000 kg
2000 kg
8000 kg
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
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 water pressure per metre length on a vertical masonry wall of dam is (where w = Specific weight of the liquid, and H = Height of the liquid)
wH/2
wH
wH2/2
wH2/4
When a body floating in a liquid, is displaced slightly, it oscillates about
C.G. of body
Center of pressure
Center of buoyancy
Metacentre
The total energy of a liquid particle in motion is equal to
Pressure energy + kinetic energy + potential energy
Pressure energy - (kinetic energy + potential energy)
Potential energy - (pressure energy + kinetic energy
Kinetic energy - (pressure energy + potential energy)
One cubic metre of water weighs
100 litres
250 litres
500 litres
1000 litres
An internal mouthpiece is said to be running free if the length of the mouthpiece is __________ the diameter of the orifice.
Less than twice
More than twice
Less than three times
More than three times
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
For hypersonic flow, the Mach number is
Unity
Greater than unity
Greater than 2
Greater than 4
Density of water is maximum at
0° C
0° K
4° C
100° C
Choose the wrong statement
The center of buoyancy is located at the center of gravity of the displaced liquid
For stability of a submerged body, the center of gravity of body must lie directly below the center of buoyancy
If C.G. and center of buoyancy coincide, the submerged body must lie at neutral equilibrium for all positions
All floating bodies are stable
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 coefficient of viscosity may be determined by
Capillary tube method
Orifice type viscometer
Rotating cylinder method
All of these
For a floating body to be in equilibrium
Meta centre should be above e.g.
Centre of buoyancy and e.g. must lie on same vertical plane
A righting couple should be formed
All of the above
According to the principle of buoyancy a body totally or partially immersed in a fluid will be lifted up by a force equal to
The weight of the body
More than the weight of the body
Less than the weight of the body
Weight of the fluid displaced by the body
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
Select the correct statement
Local atmospheric pressure depends upon elevation of locality only
Standard atmospheric pressure is the mean local atmospheric pressure a* sea level
Local atmospheric pressure is always below standard atmospheric pressure
A barometer reads the difference between local and standard atmospheric pressure
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 line of action of the buoyant force acts through the Centroid of the
Submerged body
Volume of the floating body
Volume of the fluid vertically above the body
Displaced volume of the fluid
A moving fluid mass may be brought to a static equilibrium position, by applying an imaginary inertia force of the same magnitude as that of the accelerating force but in the opposite direction. This statement is called
Pascal's law
Archimedess principle
D-Alembert's principle
None of these
The normal stress is same in all directions at a point in a fluid
Only when the fluid is frictionless
Only when the fluid is incompressible and has zero viscosity
When there is no motion of one fluid layer relative to an adjacent layer
Irrespective of the motion of one fluid layer relative to an adjacent layer
The normal stress in a fluid will be constant in all directions at a point only if
It is incompressible
It has uniform viscosity
It has zero viscosity
It is at rest