Hot wire anemometer is used to measure
Pressure in gases
Liquid discharge
Pressure in liquids
Gas velocities
Correct Answer :
D. Gas velocities
Related Questions
Flow of water in a pipe about 3 metres in diameter can be measured by
Orifice plate
Venturimeter
Rotameter
Pitot tube
The viscosity of water is __________ than that of mercury.
Higher
Lower
Same as
None of these
The resultant of all normal pressures acts
At C.G. of body
At center of pressure
Vertically upwards
At metacentre
When a body is immersed wholly or partially in a liquid, it is lifted up by a force equal to the weight of liquid displaced by the body. This statement is called
Pascal's law
Archimedess principle
Principle of floatation
Bernoulli's theorem
The meatcentric height is the distance between the
Centre of gravity of the floating body and the centre of buoyancy
Centre of gravity of the floating body and the metacentre
Metacentre and centre of buoyancy
Original centre of buoyancy and new centre of buoyancy
The maximum efficiency of transmission through a pipe is
50 %
56.7 %
66.67 %
76.66 %
The upper surface of a weir over which water flows is known is
Crest
Nappy
Sill
Weir top
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
For very great pressures, viscosity of moss gases and liquids
Remain same
Increases
Decreases
Shows erratic behaviour
The loss of head at exit of a pipe is (where v = Velocity of liquid in the pipe)
v²/2g
0.5v²/2g
0.375v²/2g
0.75v²/2g
The liquid used in manometers should have
Low density
High density
Low surface tension
High surface tension
According to Bazin's formula, the discharge over a rectangular weir is mL2g x H3/2where m is equal to
0.405 + (0.003/H)
0.003 + (0.405/H)
0.405 + (H/0.003)
0.003 + (H/0.405)
Viscosity of water in comparison to mercury is
Higher
Lower
Same
Higher/lower depending on temperature
The surface tension of mercury at normal temperature compared to that of water is
More
Less
Same
More or less depending on size of glass tube
Froude's number is the ratio of inertia force to
Pressure force
Elastic force
Gravity force
Surface tension force
The weight per unit volume of a liquid at a standard temperature and pressure is called
Specific weight
Mass density
Specific gravity
None of these
A compound pipe of diameter d1, d2 and d3 having lengths l1, l2 and l3 is to be replaced by an equivalent pipe of uniform diameter d and of the same length (l) as that of the compound pipe. The size of the equivalent pipe is given by
l/d² = (l₁/d₁²) + (l₂/d₂²) + (l₃/d₃²)
l/d³ = (l₁/d₁³) + (l₂/d₂³) + (l₃/d₃³)
l/d⁴ = (l₁/d₁⁴) + (l₂/d₂⁴) + (l₃/d₃⁴)
l/d⁵ = (l₁/d₁⁵) + (l₂/d₂⁵) + (l₃/d₃⁵)
The top of the weir over which the water flows is known as
Sill or crest
Nappe or vein
Orifice
None of these
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
A bucket of water is hanging from a spring balance. An iron piece is suspended into water without touching sides of bucket from another support. The spring balance reading will
Increase
Decrease
Remain same
Increase/decrease depending on depth of immersion
A piece of metal of specific gravity 13.6 is placed in mercury of specific gravity 13.6, what fraction of it volume is under mercury?
The metal piece will simply float over the mercury
The metal piece will be immersed in mercury by half
Whole of the metal piece will be immersed with its top surface just at mercury level
Metal piece will sink to the bottom
The error in discharge (dQ/Q) to the error in measurement of head (dH/H) over a rectangular notch is given by
dQ/Q = (1/2) × (dH/H)
dQ/Q = (3/4) × (dH/H)
dQ/Q = (dH/H)
dQ/Q = (3/2) × (dH/H)
The discharge through a siphon spillway is
Cd × a × √(2gH)
Cd × a × √(2g) × H3/2
Cd × a × √(2g) × H2
Cd × a × √(2g) × H5/2
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
For pipes, laminar flow occurs when Reynolds number is
Less than 2000
Between 2000 and 4000
More than 4000
Less than 4000
The angle of contact in case of a liquid depends upon
The nature of the liquid and the solid
The material which exists above the free surface of the liquid
Both of die above
Any one of the above
The velocity at which the flow changes from laminar flow to turbulent flow is called
Critical velocity
Velocity of approach
Sub-sonic velocity
Super-sonic velocity
The rise of liquid along the walls of a revolving cylinder about the initial level is __________ the depression of the liquid at the axis of rotation.
Same as
Less than
More than
None of these
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 hydraulic mean depth or the hydraulic radius is the ratio of
Area of flow and wetted perimeter
Wetted perimeter and diameter of pipe
Velocity of flow and area of flow
None of these