The ratio of the inertia force to the elastic force is called
Reynold's number
Froude's number
Weber's number
Mach number
Correct Answer :
D. Mach number
Related Questions
In order to increase sensitivity of U-tube manometer, one leg is usually inclined by angle θ. Sensitivity of inclined tube to sensitivity of Utube is equal to
Sinθ
1/Sinθ
Cosθ
1/Cosθ
The total pressure on the top of a closed cylindrical vessel completely filled up with a liquid is
Directly proportional to (radius)2
Inversely proportional to (radius)2
Directly proportional to (radius)4
Inversely proportional to (radius)4
The discharge through a wholly drowned orifice is given by (where H1 = Height of water (on the upstream side) above the top of the orifice, H2 = Height of water (on the downstream side) above the bottom of the orifice, and H = Difference between two water levels on either side of the orifice)
Q = Cd × bH₁ × √(2gh)
Q = Cd × bH2 × √(2gh)
Q = Cd × b (H2 - H1) × √(2gh)
Q = Cd × bH × √(2gh)
When the Mach number is less than unity, the flow is called
Sub-sonic flow
Sonic flow
Super-sonic flow
Hyper-sonic flow
The vapour pressure over the concave surface is
Less man the vapour pressure over the plane surface
Equal to the vapour pressure over the plane surface
Greater than the vapour pressure over the plane surface
Zero
In a forced vortex, the velocity of flow everywhere within the fluid is
Maximum
Minimum
Zero
Nonzero finite
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
A body floats in stable equilibrium
When its meatcentric height is zero
When the metacentre is above C.G.
When its e.g. is below its center of buoyancy
Metacentre has nothing to do with position of e.g. for determining stability
Which of the following instrument can be used for measuring speed of a submarine moving in deep sea?
Venturimeter
Orifice plate
Hot wire anemometer
Pitot tube
Flow occurring in a pipeline when a valve is being opened is
Steady
Unsteady
Laminar
Vortex
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
When the flow parameters at any given instant remain same at every point, then flow is said to be
Quasi-static
Steady state
Laminar
Uniform
Which of the following manometer has highest sensitivity?
U-tube with water
Inclined U-tube
U-tube with mercury
Micro-manometer with water
The increase of temperature results in
Increase in viscosity of gas
Increase in viscosity of liquid
Decrease in viscosity of gas
Decrease in viscosity of liquid
Stoke is the unit of
Kinematic viscosity in C. G. S. units
Kinematic viscosity in M. K. S. units
Dynamic viscosity in M. K. S. units
Dynamic viscosity in S. I. units
The fluid forces considered in the Navier Stokes equation are
Gravity, pressure and viscous
Gravity, pressure and turbulent
Pressure, viscous and turbulent
Gravity, viscous and turbulent
Fluid is a substance which offers no resistance to change of
Pressure
Flow
Shape
Volume
The coefficient of discharge for an external mouthpiece depends upon
Velocity of liquid
Pressure of liquid
Area of mouthpiece
Length of mouthpiece
Buoyant force is
The resultant force acting on a floating body
The resultant force on a body due to the fluid surrounding it
Equal to the volume of liquid displaced
The force necessary to maintain equilibrium of a submerged body
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 flow in a pipe is turbulent when Reynold number is
Less than 2000
Between 2000 and 2800
More than 2800
None of these
The velocity 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
An air vessel is provided at the summit in a siphon to
Avoid interruption in the flow
Increase discharge
Increase velocity
Maintain pressure difference
Gradually varied flow is
Steady uniform
Non-steady non-uniform
Non-steady uniform
Steady non-uniform
When the Mach number is between __________ the flow is called super-sonic flow.
1 and 2.5
2.5 and 4
4 and 6
1 and 6
Density of water is maximum at
0° C
0° K
4° C
100° C
A hemispherical tank of radius (R) has an orifice of cross-sectional area (a) at its bottom and is full of liquid. The time required to empty the tank completely is
14π R1/2/15Cd × a √(2g)
14π R3/2/15Cd × a √(2g)
14π R5/2/15Cd × a √(2g)
14π R7/2/15Cd × a √(2g)
During the opening of a valve in a pipe line, the flow is
Steady
Unsteady
Uniform
Laminar
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
A nozzle placed at the end of a water pipe line discharges water at a
Low pressure
High pressure
Low velocity
High velocity