Fanning friction factor is equal to (where, fB = Blasius friction factor) ?

Related Mcqs:

1. If Blasius or Darcy friction factor is ‘f1’ then the Fanning friction factor is equal to____________________?

   A. f1/4
   B. 4f2
   C. 2f1
   D. f1/2

2. Which of the following is the „Blasius equation‟, relating friction factor to the Reynolds number ?

   A. f = 0.079.NRe-0.25
   B. f-0.5 = 4.07 loge (NRef)-0.6
   C. Both ‘a’ and ‘b’
   D. None of these

3. A centrifugal pump is used to pump water through a horizontal distance of 150 m, and then raised to an overhead tank 10 m above. The pipe is smooth with an I.D of 50 mm. What head (m of water) must the pump generate at its exit E. to deliver water at a flow rate of 0.001 m3/s? The Fanning friction factor, f is 0.0062 ?

   A. 10 m
   B. 11 m
   C. 11.8 m
   D. 30 m

4. Fanning friction factor equation applies to the _____________ fluid flow?

   A. Non-isothermal condition of
   B. Compressible
   C. Both A. and B.
   D. Neither A. nor B.

5. What is the value of Fanning friction factor f ‘ for smooth pipe at NRe = 106 approximately ?

   A. 0.003
   B. 0.01
   C. 0.1
   D. 0.3

6. 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.

7. Friction factor for a hydraulically smooth pipe at NRe = 2100 is f1. If the pipe is further smoothened (i.e., roughness is reduced), the friction factor at the same value of NRe, will_______________?

   A. Increase
   B. Decrease
   C. Remain unchanged
   D. Increase or decrease depending on the pipe material

8. If three pipes of different diameters, lengths & friction factors are connected in parallel, then (where, Q = flow rate, V= fluid velocity f = friction factor). ?

   A. Q = Q1 + Q2 + Q3
   B. V1 = V2 = V3
   C. Q1 = Q2 = Q3
   D. f = f1 + f2 + f3

9. Colebrook equation for friction factor in turbulent flow is given by, f-0.5 = -4 loge [(ε/D) + (1.26/NRe √F). It reduces to Nikuradse equation for a value of (ϵ/D) equal to __________________?

   A. 0
   B. 1
   C. ∞
   D. 0.5

10. Friction produced by the formation of wakes is called the ______________ friction?

    A. Disk
    B. Skin
    C. Form
    D. None of these