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
Correct Answer :
C. Both of die above
Related Questions
The divergent portion of a Venturimeter is made longer than convergent portion in order to
Avoid the tendency of breaking away the stream of liquid
To minimise frictional losses
Both (A) and (B)
None of these
The centre of gravity of the volume of the liquid displaced by an immersed body is called
Centre of gravity
Centre of pressure
Metacentre
Centre of buoyancy
An air vessel is provided at the summit in a siphon to
Avoid interruption in the flow
Increase discharge
Increase velocity
Maintain pressure difference
Which of the following statement is wrong?
A flow whose streamline is represented by a curve is called two dimensional flow.
The total energy of a liquid particle is the sum of potential energy, kinetic energy and pressure energy.
The length of divergent portion in a Venturimeter is equal to the convergent portion.
A pitot tube is used to measure the velocity of flow at the required point in a pipe.
Principle of similitude forms the basis of
Comparing two identical equipments
Designing models so that the result can be converted to prototypes
Comparing similarity between design and actual equipment
Hydraulic designs
The resultant upward pressure of the fluid on an immersed body due to its tendency to uplift the submerged body is called
Up-thrust
Reaction
Buoyancy
Metacentre
Flow of water in a pipe about 3 metres in diameter can be measured by
Orifice plate
Venturimeter
Rotameter
Pitot tube
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
In an immersed body, centre of pressure is
At the centre of gravity
Above the centre of gravity
Below be centre of gravity
Could be above or below e.g. depending on density of body and liquid
A nozzle placed at the end of a water pipe line discharges water at a
Low pressure
High pressure
Low velocity
High velocity
Liquids
Cannot be compressed
Occupy definite volume
Are not affected by change in pressure and temperature
None of the above
To avoid vaporisation in the pipe line, the pipe line over the ridge is laid such that it is not more than
2.4 m above the hydraulic gradient
6.4 m above the hydraulic gradient
10.0 m above the hydraulic gradient
5.0 above the hydraulic gradient
Newton's law of viscosity is a relationship between
Shear stress and the rate of angular distortion
Shear stress and viscosity
Shear stress, velocity and viscosity
Pressure, velocity and viscosity
Falling drops of water become spheres due to the property of
Adhesion
Cohesion
Surface tension
Viscosity
The length of the divergent cone in a Venturimeter is __________ that of the convergent cone.
Equal to
Double
Three to four times
Five to six times
The volume of a fluid __________ as the pressure increases.
Remains same
Decreases
Increases
None of these
The kinematic viscosity is the
Ratio of absolute viscosity to the density of the liquid
Ratio of density of the liquid to the absolute viscosity
Product of absolute viscosity and density of the liquid
Product of absolute viscosity and mass of the liquid
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
Coefficient of resistance is the ratio of
Actual velocity of jet at vena-contracta to the theoretical velocity
Area of jet at vena-contracta to the area of orifice
Loss of head in the orifice to the head of water available at the exit of the orifice
Actual discharge through an orifice to the theoretical discharge
In the case of steady flow of a fluid, the acceleration of any fluid particle is
Constant
Variable
Zero
Zero under limiting conditions
The product of mass and acceleration of flowing liquid is called
Inertia force
Viscous force
Gravity force
Pressure force
The Newton's law of resistance is based on the assumption that the
Planes of the body are completely smooth
Space around the body is completely filled with the fluid
Fluid particles do not exert any influence on one another
All of the above
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
When a vertical wall is subjected to pressures due to liquid on both sides, the resultant pressure is the __________ of the two pressures.
Sum
Difference
Arithmetic mean
Geometric mean
The power absorbed (in watts) in overcoming the viscous resistance of a footstep bearing is
μ π³ N² R² /1800 t
μ π³ N² R⁴ /1800 t
μ π³ N² R² /3600 t
μ π³ N² R⁴ /3600 t
The power transmitted through the pipe is maximum when the head lost due to friction is equal to
One-fourth of the total supply head
One-third of the total supply head
One-half of the total supply head
Two-third of the total supply head
When the Mach number is less than unity, the flow is called
Sub-sonic flow
Sonic flow
Super-sonic flow
Hyper-sonic flow
The most efficient section of a channel is
Triangular
Rectangular
Square
Trapezoidal
The discharge of a depressed nappe is 6 to 7 percent __________ that of a free nappe.
Less than
More than
Equal to
None of these
In a lock-gate, the reaction between two gates is (where P = Resultant pressure on the lock gate, and α = Inclination of the gate with the normal to the side of the lock)
p/sinα
2p/sinα
p/2sinα
2p/sin (α/2)