In the complete turbulence zone (in rough pipes), the____________________?

Related Mcqs:

1. 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

2. 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.

3. A pipe of I.D. 4 m is bifurcated into two pipes of I.D. 2 m each. If the average velocity of water flowing through the main pipe is 5 m/sec, the average velocity through the bifurcated pipes is__________________?

   A. 20 m/sec
   B. 10 m/sec
   C. 5 √2 m/sec
   D. 5 m/sec

4. In isotropic turbulence, the _____________ are equal to each other?

   A. Temporal velocity components
   B. Mean square of velocity fluctuations in the three co-ordinate directions
   C. Root mean square of velocity fluctuations in the three co-ordinate directions
   D. None of these

5. Isotropic turbulence occurs __________________?

   A. Where there is no velocity gradient
   B. At higher temperatures
   C. Only in Newtonian fluids
   D. None of these

6. In turbulent flow, a rough pipe has the same friction factor as a smooth pipe____________________?

   A. In the zone of complete turbulence
   B. When the roughness projections are much smaller than the thickness of the laminar film
   C. Everywhere in the transition zone
   D. When the friction factor is independent of the Reynold’s number

7. 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.

8. The line of action of the buoyant force acts through the____________________?

   A. Centroid of the displaced volume of fluid
   B. Centre of gravity of a submerged body
   C. Centroid of the volume of any floating body
   D. None of these

9. Dean number is concerned with the____________________?

   A. Fluid-particle interaction
   B. Fluid flow through helical pipes
   C. Power consumption in agitated vessels
   D. Psychrometry

10. With diminishing cross-sectional area in case of subsonic flow in a converging nozzle, the____________________?

    A. Velocity increases
    B. Pressure decreases
    C. Both A. & B.
    D. Neither A. nor B.