Fluid Mechanics

Question: In case of isentropic flow, the speed of sound in an ideal gas is proportional to (where M = molecular weight of the gas)
[A].

1/M

[B].

M

[C].

1/M

[D].

M

Answer: Option A

Explanation:

No answer description available for this question.

Question: Centrifugal pumps as compared to reciprocating pumps
[A].

run at a lower speed for the same discharge.

[B].

do not need priming.

[C].

deliver fluid with pulsating/fluctuating discharge.

[D].

can be run with discharge line valve closed for a short interval.

Answer: Option D

Explanation:

No answer description available for this question.

Question: The capacity of a centrifugal pump Can be increased by increasing the
[A].

impeller diameter or speed.

[B].

number of pumps and joining them in series,

[C].

number of pumps and joining them in parallel.

[D].

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

Answer: Option D

Explanation:

No answer description available for this question.

Question: Which of the following relationship is valid for the equilibrium position of the float in a rotameter ?(where, Df= Drag force on the float Bf = Buoyant force on the float Wf = Weight of the float)
[A].

Df + Bf = Wf

[B].

Df = Bf + Wf

[C].

Df + Bf + Wf =0

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.

Question: The boundary layer is that part of a moving fluid, in which the fluid velocity is
[A].

affected by the fluid flow pressure.

[B].

constant.

[C].

affected by the presence of a solid boundary.

[D].

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

Answer: Option C

Explanation:

No answer description available for this question.

Question: Bernoulli’s equation for fluid flow is derived following certain assumptions. Out of the assumptions listed below, which set of assumptions is used in derivation of Bernoulli’s equation ?A. Fluid flow is frictionless & irrotational. B. Fluid flow is steady. C. Fluid flow is uniform & turbulent.D. Fluid is compressible.E. Fluid is incompressible.
[A].

A, C, D

[B].

B, D, E

[C].

A, B, E

[D].

A, D, E

Answer: Option C

Explanation:

No answer description available for this question.

Question: Bernoulli’s equation for steady, frictionless, continuous flow states that the __________ at all sections is same.
[A].

total pressure

[B].

total energy

[C].

velocity head

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: Kinetic energy of fluid per unit weight represented by the velocity head is given by
[A].

2v2/gc

[B].

v2/2gc

[C].

ρv2/gc

[D].

ρ.v2/2gc

Answer: Option B

Explanation:

No answer description available for this question.

Question: Consider two pipes of same length and diameter through which water is passed at the same velocity. The friction factor for rough pipe is f1 and that for smooth pipe is f2. Pick out the correct statement.
[A].

f1 = f2

[B].

f1 < f2

[C].

f1 > f2

[D].

data not sufficient to relate f1 & f2

Answer: Option C

Explanation:

No answer description available for this question.

Question: N. second/m2 is
[A].

the S.I. unit of dynamic viscosity.

[B].

the S.I. unit of kinematic viscosity.

[C].

equivalent to one poise.

[D].

equivalent to one stoke.

Answer: Option A

Explanation:

No answer description available for this question.