The Reynold's number of a ship is __________ to its velocity and length.
Directly proportional
Inversely proportional
Square root of velocity
None of these
Correct Answer :
A. Directly proportional
Related Questions
The power transmitted through a pipe is (where w = Specific weight in N/m3, and Q = Discharge in m3/s)
w × Q × H
w × Q × hf
w × Q (H - hf)
w × Q (H + hf)
One poise is equal to
0.1 N-s/m2
1 N-s/m2
10 N-s/m2
100 N-s/m2
Practical fluids
Are viscous
Possess surface tension
Are compressible
Possess all the above properties
Choose the wrong statement
Fluids are capable of flowing
Fluids conform to the shape of the containing vessels
When in equilibrium, fluids cannot sustain tangential forces
When in equilibrium, fluids can sustain shear forces
The pressure intensity in kN/m2 (or kPa) at any point in a liquid is (where w = Specific weight of liquid, and h = Depth of liquid from the surface)
w
wh
w/h
h/w
Falling drops of water become spheres due to the property of
Surface tension of water
Compressibility of water
Capillarity of water
Viscosity of water
The conditions for the stable equilibrium of a floating body are
The metacentre should lie above the center of gravity
The center of buoyancy and the center of gravity must lie on the same vertical line
A righting couple should be formed
All the above are correct
The flow in which the velocity vector is identical in magnitude and direction at every point, for any given instant, is known as
One dimensional flow
Uniform flow
Steady flow
Turbulent flow
In a free nappe,
The pressure below the nappe is atmospheric
The pressure below the nappe is negative
The pressure above the nappe is atmospheric
The pressure above the nappe is negative
A structure used to dam up a stream or river over which the water flows is called
Orifice
Notch
Weir
Dam
One cubic metre of water weighs
100 litres
250 litres
500 litres
1000 litres
Ratio of inertia force to elastic force is known as
Mach number
Froude number
Reynolds number
Weber's number
A balloon lifting in air follows the following principle
Law of gravitation
Archimedes principle
Principle of buoyancy
All of the above
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
Liquids transmit pressure equally in all the directions. This is according to
Boyle's law
Archimedes principle
Pascal's law
Newton's formula
Non 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
Velocity, depth, pressure, etc. change from point to point in the fluid flow.
The fluid particles move in plane or parallel planes and the streamline patterns are identical in each plane
The force exerted by a moving fluid on an immersed body is directly proportional to the rate of change of momentum due to the presence of the body. This statement is called
Newton's law of motion
Newton's law of cooling
Newton's law of viscosity
Newton's law of resistance
The specific gravity of an oil whose specific weight is 7.85 kN/m3, is
0.8
1
1.2
1.6
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
Bernoulli equation deals with the law of conservation of
Mass
Momentum
Energy
Work
When a body is placed over a liquid, it will sink down if
Gravitational force is equal to the up-thrust of the liquid
Gravitational force is less than the up-thrust of the liquid
Gravitational force is more than the up-thrust of the liquid
None of the above
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)
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
At the center line of a pipe flowing under pressure where the velocity gradient is zero, the shear stress will be
Minimum
Maximum
Zero
Could be any value
The velocity of the liquid flowing through the divergent portion of a Venturimeter
Remains constant
Increases
Decreases
Depends upon mass of liquid
According to equation of continuity,
w1a1 = w2a2
w1v1 = w2v2
a1v1 = a2v2
a1/v1 = a2/v2
The resultant upward pressure of a fluid on a floating body is equal to the weight of the fluid displaced by the body. This definition is according to
Buoyancy
Equilibrium of a floating body
Archimedes' principle
Bernoulli's theorem
The value of coefficient of velocity for a sharp edged orifice __________ with the head of water.
Decreases
Increases
Remain same
None of these
The velocity corresponding to Reynold number of 2800, is called
Sub-sonic velocity
Super-sonic velocity
Lower critical velocity
Higher critical velocity
The total pressure on the top of a closed cylindrical vessel of radius (r) completely filled up with liquid of specific weight (w) and rotating at (ω) rad/s about its vertical axis, is
π w ω² r²/4g
π w ω² r³/4g
π w ω² r⁴/4g
π w ω² r²/2g