The velocity at which the laminar flow stops, is known as
Velocity of approach
Lower critical velocity
Higher critical velocity
None of these
Correct Answer :
B. Lower critical velocity
Related Questions
Center of buoyancy is the
Centroid of the displaced volume of fluid
Center of pressure of displaced volume
Does not exist
None of the above
A liquid would wet the solid, if adhesion forces as compared to cohesion forces are
Less
More
Equal
Less at low temperature and more at high temperature
The product of mass and acceleration of flowing liquid is called
Inertia force
Viscous force
Gravity force
Pressure force
The discharge through a small rectangular orifice is given by (where Cd = Coefficient of discharge for the orifice, a = Cross-sectional area of the orifice, h = Height of the liquid above the centre of the orifice)
Q = Cd × a × 2gh
Q = (2/3). Cd × a × h
Q = (Cd × a)/√(2gh)
Q = (3Cd × a)/√(2h)
Reynold's number is the ratio of inertia force to
Pressure force
Elastic force
Gravity force
Viscous force
The dynamic viscosity of gases __________ with rise in temperature.
Remain unaffected
Increases
Decreases
None of these
The discharge in an open channel corresponding to critical depth is
Zero
Minimum
Maximum
None of these
Operation of McLeod gauge used for low pressure measurement is based on the principle of
Gas law
Boyle's law
Charles law
Pascal's law
A nozzle is generally made of
Cylindrical shape
Convergent shape
Divergent shape
Convergent-divergent shape
A flow is called hyper-sonic, if the Mach number is
Less than unity
Unity
Between 1 and 6
None of these
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
Surface energy per unit area of a surface is numerically equal to
Atmospheric pressure
Surface tension
Force of adhesion
Force of cohesion
If no resistance is encountered by displacement, such a substance is known as
Fluid
Water
Gas
Ideal fluid
For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
The pressure of liquid at throat in a Venturimeter is __________ than that at inlet.
Higher
Lower
Same
None of these
A vertical wall is subjected to a pressure due to one kind of liquid, on one of its sides. The total pressure on the wall per unit length is (where w = Specific weight of liquid, and H = Height of liquid)
wH
wH/2
wH2/2
wH2/3
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
A submerged body is said to be in a stable equilibrium, if its centre of gravity __________ the centre of buoyancy.
Coincides with
Lies below
Lies above
None of these
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)
An open tank containing liquid is moving with an acceleration on an inclined plane. The inclination of the free surface of the liquid will be __________ to the acceleration of the tank.
Equal to
Directly proportional
Inversely proportional
None of these
One stoke is equal to
10-2 m2/s
10-3 m2/s
10-4 m2/s
10-6 m2/s
The bulk modulus of elasticity
Has the dimensions of 1/pressure
Increases with pressure
Is large when fluid is more compressible
Is independent of pressure and viscosity
A vessel of 4 m3 contains oil which weighs 30 kN. The specific weight of the oil is
4.5 kN/m3
6 kN/m3
7.5 kN/m3
10 kN/m3
For similarity, in addition to models being geometrically similar to prototype, the following in both cases should also be equal
Ratio of inertial force to force due to viscosity
Ratio of inertial force to force due to gravitation
Ratio of inertial force to force due to surface tension
All the four ratios of inertial force to force due to viscosity, gravitation, surface tension, and elasticity
The force per unit length is the unit of
Surface tension
Compressibility
Capillarity
Viscosity
The resultant of all normal pressures acts
At C.G. of body
At center of pressure
Vertically upwards
At metacentre
The specific weight of water is 1000 kg/m3
At normal pressure of 760 mm
At 4°C temperature
At mean sea level
All the above
A vertical wall is subjected to a pressure due to one kind of liquid, on one of its sides. The total pressure on the wall acts at a distance __________ from the liquid surface.
H/3
H/2
2H/3
3H/4
The ratio of the inertia force to the __________ is called Euler's number.
Pressure force
Elastic force
Surface tension force
Viscous force
A Piezometer tube is used only for measuring
Low pressure
High pressure
Moderate pressure
Vacuum pressure