Fluid Mechanics

Question: Cavitation occurs in a centrifugal pump when the suction pressure is
[A].

less than the vapour pressure of the liquid at that temperature.

[B].

greater than the vapour pressure of the liquid at that temperature.

[C].

equal to the vapour pressure.

[D].

equal to the developed head.

Answer: Option A

Explanation:

No answer description available for this question.

Question: In case of a pipe exit fitted with a nozzle, the
[A].

conversion of kinetic head to pressure head is facilitated.

[B].

conversion of pressure head to kinetic head is facilitated.

[C].

power transmitted through the nozzle is maximum, when the head lost due to friction in the pipe is equal to one third of the total supply head.

[D].

both (b) and (c)

Answer: Option D

Explanation:

No answer description available for this question.

Question: In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of
[A].

relative roughness.

[B].

absolute roughness.

[C].

friction co-efficient for flows at equal Reynold number.

[D].

all (a), (b) & (c).

Answer: Option C

Explanation:

No answer description available for this question.

Question: Fluid flow in a/an __________ is an example of pressure flow.
[A].

partially filled pipeline

[B].

pipe

[C].

open channel

[D].

river.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Dean number is concerned with the
[A].

fluid-particle interaction.

[B].

fluid flow through helical pipes.

[C].

power consumption in agitated vessels.

[D].

psychrometry.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Lower BWG means __________ of the tube.
[A].

lower thickness

[B].

lower cross-section

[C].

outer diameter

[D].

inner diameter

Answer: Option B

Explanation:

No answer description available for this question.

Question: Curve III in the above diagram represents a/an
[A].

dilatent fluid

[B].

pseudo plastic fluid

[C].

ideal plastic

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: During fluid flow, variation of shear stress(τ) with velocity gradientat constant pressure temperature is shown below in the figureIn the above figure, Binghom plastic is represented by the curve .
[A].

V

[B].

II

[C].

III

[D].

I

Answer: Option B

Explanation:

No answer description available for this question.

Question: In case of unsteady fluid flow, conditions & flow pattern change with the passage of time at a position in a flow situation. Which of the following is an example of unsteady flow?
[A].

Discharge of water by a centrifugal pump being run at a constant rpm.

[B].

Water flow in the suction and discharge pipe of a reciprocating pump.

[C].

Water discharge from a vertical vessel in which constant level is maintained.

[D].

Low velocity flow of a highly viscous liquid through a hydraulically smooth pipe.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Fluid flow at increasing rate through a diverging pipe is an example of __________ flow.
[A].

steady uniform

[B].

non-steady uniform

[C].

steady non-uniform

[D].

non-steady non-uniform

Answer: Option D

Explanation:

No answer description available for this question.