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Question: For the manometer set up shown in the figure, the pressure difference PA – PB is given by
[A].

(ρH – ρair)gH

[B].

(ρH – ρL)gH

[C].

(ρH – ρL) gH + (ρL – ρair) . g(L – H)

[D].

(ρH – ρL) gL + (ρL – ρair)gH

Answer: Option A

Explanation:

No answer description available for this question.

Question: Molten soap mass is transported by a __________ pump.
[A].

diaphragm

[B].

reciprocating

[C].

gear

[D].

centrifugal

Answer: Option D

Explanation:

No answer description available for this question.

Question: A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun’s equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 x 103 VOM + 10.94 x 106 V2OM (SI units) If water is to be used as the fluidising medium, in actual operation, the above bed has a height = 1 m. What is the porosity of the fluidised bed ?
[A].

0.2

[B].

0.5

[C].

0.7

[D].

0.8

Answer: Option C

Explanation:

No answer description available for this question.

Question: A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun’s equation for the above fluid-particle system (in SI units) is given below : Δ P/L = 375 x 103 VOM + 10.94 x 106 V2OM (SI units) If water is to be used as the fluidising medium, the minimum fluidisation velocity, VOM is
[A].

12 mm/s

[B].

16 mm/s

[C].

24 mm/s

[D].

28 mm/s

Answer: Option B

Explanation:

No answer description available for this question.

Question: A fluid element has a velocity V = -y2 . xi + 2yx2 . j. The motion at (x, y) = (l/2, 1) is
[A].

rotational and incompressible

[B].

rotational and compressible

[C].

irrotational and compressible

[D].

irrotational and incompressible

Answer: Option B

Explanation:

No answer description available for this question.

Question: A lubricant 100 times more viscous than water would have a viscosity (in Pa.s)
[A].

0.01

[B].

0.1

[C].

1

[D].

10

Answer: Option B

Explanation:

No answer description available for this question.

Question: A gas (density = 1.5 kg/m3 , viscosity = 2x 10-5 kg/m.s) flowing through a packed bed (particle size = 0.5 cm, porosity = 0.5) at a superficial velocity of 2 m/s causes a pressure drop of 8400 Pa/m. The pressure drop for another gas, with density of 1.5kg/m3and viscosity of 3 x 10-5kg/m.s flowing at 3 m/s will be
[A].

8400 Pa/m

[B].

12600 Pa/m

[C].

18900 Pa/m

[D].

16800 Pa/m

Answer: Option B

Explanation:

No answer description available for this question.

Question: For turbulent flow of an incompressible fluid through a pipe, the flow rate Q is proportional to (Δ P)n, where ΔP is the pressure drop. The value of exponent ‘n’ is
[A].

1

[B].

0

[C].

< 1

[D].

> 1

Answer: Option C

Explanation:

No answer description available for this question.

Question: For flow past a flat plate, if x is the distance along the plate in the direction of flow, the boundary layer thickness is proportional to
[A].

x

[B].

1/x

[C].

x

[D].

1/x

Answer: Option A

Explanation:

No answer description available for this question.

Question: With increasing flow rate, the hydraulic efficiency of a centrifugal pump
[A].

monotonically decreases.

[B].

decreases and then increases.

[C].

remains constant.

[D].

increases and then decreases.

Answer: Option A

Explanation:

No answer description available for this question.