Fluid Mechanics MCQs

Question 1

Small pressure differences in liquids is measured using a/an

Accepted Answer

Inclined tube manometer

Answer

U-tube manometer

Answer

Pitot tube

Answer

None of these

Question 2

Bernoulli's equation accounts for the

Accepted Answer

Different forms of mechanical energy

Answer

Various momentums

Answer

Various masses

Answer

None of these

Question 3

For steady ideal fluid flow, the Bernoulli's equation states that the

Accepted Answer

Energy is constant along a stream line, but may vary across stream lines

Answer

Velocity is constant along a stream line

Answer

Energy is constant throughout the fluid

Answer

None of these

Question 4

Which of the following is not dimension-less?

Accepted Answer

Kinematic viscosity

Answer

Froude number

Answer

Pressure co-efficient

Answer

None of these

Question 5

Turbulent flow generally occurs for cases involving

Accepted Answer

None of these

Answer

Highly viscous fluid

Answer

Very narrow passages

Answer

Very slow motion

Question 6

Where does the maximum stress occur in case of laminar flow of incompressible fluid in a closed conduit of diameter 'd'?

Accepted Answer

At the wall

Answer

At the centre

Answer

At $$\frac{{	ext{d}}}{4}$$ from the wall

Answer

At $$\frac{{	ext{d}}}{8}$$ from the wall

Question 7

The ratio of maximum to average velocity in case of streamline flow between parallel plates is

Accepted Answer

1.5

Answer

1

Answer

2

Answer

2.5

Question 8

Pick out the wrong statement.

Accepted Answer

With increase in the Mach number > 0.6, the drag co-efficient decreases in case of compressible fluids

Answer

The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonion fluids is $$\frac{{	ext{D}}}{{4{	ext{L}}}} \cdot \Delta {	ext{p}}$$

Answer

In the equation, $$	au \cdot {{	ext{g}}_{	ext{c}}} = {	ext{k}} \cdot {\left( {\frac{{{	ext{du}}}}{{{	ext{dy}}}}} ight)^{	ext{n}}}$$ the value of the value of 'n' for pseudoplastic and dilatant fluids are 1 respectively.

Answer

Shear stress for Newtonion fluid is proportional to the rate of shear in the direction perpendicular to motion

Question 9

The pressure head of a flow meter remains constant for

Accepted Answer

Rotameter

Answer

Venturimeter

Answer

Orificemeter

Answer

Pitot tube