During ageing of fluid carrying pipes, the (A) Pipe becomes smoother with use (B) Friction factor increases linearly with time (C) Absolute roughness decreases with time (D) Absolute roughness increases linearly with time

During ageing of fluid carrying pipes, the
(A) Pipe becomes smoother with use
(B) Friction factor increases linearly with time
(C) Absolute roughness decreases with time
(D) Absolute roughness increases linearly with time
by

1 Answer

Answer :

(D) Absolute roughness increases linearly with time
by

Related questions

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)

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Last Answer : (C) Friction co-efficient for flows at equal Reynold number

Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

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Friction factor for fluid flow in pipe does not depend upon the (A) Pipe length (B) Pipe roughness (C) Fluid density & viscosity (D) Mass flow rate of fluid

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Last Answer : A) Pipe length

In the complete turbulence zone (in rough pipes), the (A) Rough and smooth pipes have the same friction factor (B) Laminar film covers the roughness projections (C) Friction factor depends upon NRe only (D) Friction factor is independent of the relative roughness

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The friction factor is (A) Always inversely proportional to the Reynolds number (B) Not dimensionless (C) Not dependent on the roughness of the pipe (D) None of these

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