Hydraulics And Fluid Mechanics Set 7 MCQs

Q1 | 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 acts at a distance __________ from the liquid surface.

H/3

H/2

2H/3

3H/4

Q2 | An ideal flow of any fluid must fulfill the following

Newton's law of motion

Newton's law of viscosity

Pascal' law

Continuity equation

Q3 | The flow in a pipe or channel is said to be uniform when

The liquid particles at all sections have the same velocities

The liquid particles at different sections have different velocities

The quantity of liquid flowing per second is constant

Each liquid particle has a definite path

Q4 | Surface tension

Acts in the plane of the interface normal to any line in the surface

Is also known as capillarity

Is a function of the curvature of the interface

Decreases with fall in temperature

Q5 | Select the wrong statement

An equivalent pipe is treated as an ordinary pipe for all calculations

The length of an equivalent pipe is equal to that of a compound pipe

The discharge through an equivalent pipe is equal to that of a compound pipe

The diameter of an equivalent pipe is equal to that of a compound pipe

Q6 | manometers because Alcohol is used in

It has low vapour pressure

It is clearly visible

It has low surface tension

It can provide longer column due to low density

Q7 | If no resistance is encountered by displacement, such a substance is known as

Fluid

Water

Gas

Ideal fluid

Q8 | 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

Q9 | The viscosity of water is __________ than that of mercury.

Higher

Lower

Same as

None of these

Q10 | Surface energy per unit area of a surface is numerically equal to

Atmospheric pressure

Surface tension

Force of adhesion

Force of cohesion

Q11 | The specific weight of sea water is __________ that of pure water.

Same as

Less than

More than

None of these

Q12 | Which of the following instruments is used to measure flow on the application of Bernoulli's theorem?

Venturimeter

Orifice plate

Nozzle

All of the above

Q13 | The depth of the centre of pressure on a vertical rectangular gate 8 m wide and 6 m high, when the water surface coincides with the top of the gate, is

2.4 m

3.0 m

4.0 m

5.0 m

Q14 | An internal mouthpiece is said to be running free if the length of the mouthpiece is __________the diameter of the orifice.

Less than twice

More than twice

Less than three times

More than three times

Q15 | An ideal flow of any fluid must satisfy

Pascal law

Newton's law of viscosity

Boundary layer theory

Continuity equation

Q16 | The height of a water column equivalent to a pressure of 0.15 MPa is

15.3 m

25.3 m

35.3 m

45.3 m

Q17 | The region between the separation streamline and the boundary surface of the solid body isknown as

Wake

Drag

Lift

Boundary layer

Q18 | Froude number is significant in

Supersonics, as with projectile and jet propulsion

Full immersion or completely enclosed flow, as with pipes, aircraft wings, nozzles etc.

Simultaneous motion through two fluids where there is a surface of discontinuity, gravity forces, and wave making effect, as with ship's hulls

All of the above

Q19 | The ratio of specific weight of a liquid to the specific weight of pure water at a standardtemperature is called

Density of liquid

Specific gravity of liquid

Compressibility of liquid

Surface tension of liquid

Q20 | A hydraulic press has a ram of 15 cm diameter and plunger of 1.5 cm. It is required to lift a weight of 1 tonne. The force required on plunger is equal to

10 kg

100 kg

1000 kg

1 kg

Q21 | The total head of a liquid particle in motion is equal to

Pressure head + kinetic head + potential head

Pressure head - (kinetic head + potential head)

Potential head - (pressure head + kinetic head)

Kinetic head - (pressure head + potential head)

Q22 | Free surface of a liquid tends to contract to the smallest possible area due to force of

Surface tension

Viscosity

Friction

Cohesion

Q23 | The Metacentric heights of two floating bodies A and B are 1 m and 1.5 m respectively. Select thecorrect statement.

The bodies A and B have equal stability

The body A is more stable than body B

The body B is more stable than body A

The bodies A and B are unstable

Q24 | 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

Q25 | The total pressure on a horizontally immersed surface is (where w = Specific weight of the liquid, A = Area of the immersed surface, and x = Depth of the centre of gravity of the immersed surface from the liquid surface)

wA

wx

wAx

wA/x