The pressure of air __________ with the increase of height from the surface of the earth.
Does not change
Decreases
Increases
None of these
Correct Answer :
B. Decreases
Related Questions
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
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
When a plate is immersed in a liquid parallel to the flow, it will be subjected to a pressure __________ that if the same plate is immersed perpendicular to the flow.
Less than
More than
Equal to
None 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
When a cylindrical vessel of radius (r) containing liquid is revolved about its vertical axis ω rad/s, then depth of parabola which the liquid assumes is
ω.r/2g
ω².r²/2g
ω.r/4g
ω².r²/4g
Center of pressure on an inclined plane is
At the Centroid
Above the Centroid
Below the Centroid
At metacentre
The value of coefficient of velocity for a sharp edged orifice __________ with the head of water.
Decreases
Increases
Remain same
None of these
Specific weight of sea water is more that of pure water because it contains
Dissolved air
Dissolved salt
Suspended matter
All of the above
If 850 kg liquid occupies volume of one cubic meter, men 0.85 represents its
Specific weight
Specific mass
Specific gravity
Specific density
A ship whose hull length is 100 m is to travel at 10 m/sec. For dynamic similarity, at what velocity should a 1:25 model be towed through water?
10 m/sec
25 m/sec
2 m/sec
50 m/sec
When a body, floating in a liquid, is given a small angular displacement, it starts oscillating about a point known as
Centre of pressure
Centre of gravity
Centre of buoyancy
Metacentre
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
When a cylindrical vessel, containing some liquid, is rotated about its vertical axis, the liquid surface is depressed down at the axis of its rotation and rises up near the walls of the vessel on all sides. This type of flow is known as
Steady flow
Turbulent flow
Vortex flow
Uniform flow
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
For hypersonic flow, the Mach number is
Unity
Greater than unity
Greater than 2
Greater than 4
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
Which of the following statement is correct?
In a compressible flow, the volume of the flowing liquid changes during the flow
A flow, in which the volume of the flowing liquid does not change, is called incompressible flow
When the particles rotate about their own axes while flowing, the flow is said to be rotational flow
All of the above
Coefficient of discharge Cd is equal to (where Cc = Coefficient of contraction, Cv = Coefficient of velocity, and Cr = Coefficient of resistance)
Cc × Cv
Cc × Cr
Cv × Cr
Cc/Cr
A piece weighing 3 kg in air was found to weigh 2.5 kg when submerged in water. Its specific gravity is
1
5
7
6
Bernoulli equation deals with the law of conservation of
Mass
Momentum
Energy
Work
According to Darcy's formula, the loss of head due to friction in the pipe is (where f = Darcy's coefficient, l = Length of pipe, v = Velocity of liquid in pipe, and d = Diameter of pipe)
flv²/2gd
flv²/gd
3flv²/2gd
4flv²/2gd
In order to measure the flow with a Venturimeter, it is installed in
Horizontal line
Inclined line with flow upwards
Inclined line with flow downwards
Any direction and in any location
In a depressed 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
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
For pipes, turbulent flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
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
According to Bernoulli's equation
Z + p/w + v²/2g = constant
Z + p/w - v²/2g = constant
Z - p/w + v²/2g = constant
Z - p/w - v²/2g = constant
The theoretical velocity of jet at vena contracta is (where H = Head of water at vena contracta)
2gH
H × √(2g)
2g × √H
√(2gh)
The length AB of a pipe ABC in which the liquid is flowing has diameter (d1) and is suddenly enlarged to diameter (d2) at B which is constant for the length BC. The loss of head due to sudden enlargement is
(v₁ - v₂)²/g
(v₁² - v₂²)/g
(v₁ - v₂)²/2g
(v₁² - v₂²)/2g
The discharge through a siphon spillway is
Cd × a × √(2gH)
Cd × a × √(2g) × H3/2
Cd × a × √(2g) × H2
Cd × a × √(2g) × H5/2