Fluid Mechanics MCQs

Question 1

Hydraulic radius is the ratio of

Accepted Answer

Flow area to wetted perimeter

Answer

Wetted perimeter to flow area

Answer

Flow area to square of wetted perimeter

Answer

Square root of flow area to wetted perimeter

Question 2

Prandtl number is a measure of the

Accepted Answer

Heat conduction to viscosity of a fluid

Answer

$$\frac{{{{	ext{C}}_{	ext{p}}}}}{{{{	ext{C}}_{	ext{v}}}}}$$ of a fluid

Answer

Elastic force to pressure force in the fluid flow

Answer

Inertial force to elastic force in the fluid flow

Question 3

Mass velocity is independent of temperature & pressure, when the flow is

Accepted Answer

Steady and the cross-section is unchanged

Answer

Unsteady through unchanged cross-section

Answer

Steady through changing cross-section

Answer

Unsteady and the cross-section is changed

Question 4

What causes convective acceleration in fluid flow?

Accepted Answer

Non-uniformity of flow

Answer

Steep slope in flow

Answer

Unsteady nature of flow

Answer

Turbulence in flow

Question 5

Normal depth in open channel flow is the depth of flow in the channel

Accepted Answer

Corresponding to uniform flow

Answer

Measured normal to the channel bed

Answer

Corresponding to steady flow

Answer

None of these

Question 6

Which of the following is not concerned with the fluid-particle interaction?

Accepted Answer

Weber number

Answer

Drag co-efficient

Answer

Froude number

Answer

Galileo number

Question 7

Which of the following is dimensionless?

Accepted Answer

Fanning friction factor

Answer

Angular velocity

Answer

Specific volume

Answer

None of these

Question 8

The pressure co-efficient is the ratio of pressure forces to __________ forces.

Accepted Answer

Inertial

Answer

Viscous

Answer

Gravity

Answer

Surface tension

Question 9

Pressure co-efficient is the ratio of pressure forces to __________ forces.

Accepted Answer

Inertial

Answer

Gravity

Answer

Viscous

Answer

None of these