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
Related Mcqs:
- Fanning friction factor is equal to (where, fB = Blasius friction factor) ?
A. fB/4
B. fB/2
C. 4fB
D. 2fB - 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 - The equation relating friction factor to Reynold number, f-0.5 = 4 loge (NRe/√f)-0.4, is called the _____________ equation?
A. Nikuradse
B. Von-Karman
C. Blasius
D. Colebrook - 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 - 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 - For a given Reynolds number, in a hydraulically smooth pipe, further smoothening ____________ the friction factor?
A. Brings about no further reduction of
B. Increases
C. Decreases
D. None of these - 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 - 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. - Stoke’s equation is valid in the Reynolds number range__________________?
A. 0.01 to 0.1
B. 0.1 to 2
C. 2 to 10
D. 10 to 100 - Friction produced by the formation of wakes is called the ______________ friction?
A. Disk
B. Skin
C. Form
D. None of these
