For the same terminal conditions and fitting size, the least friction loss is incurred in a/an ?

Related Mcqs:

1. 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

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

   A. fB/4
   B. fB/2
   C. 4fB
   D. 2fB

3. 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

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

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

5. 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

6. For the same terminal conditions and valve size, the pressure drop in a fully opened globe valve as compared to that in a gate valve is___________________?

   A. More
   B. Less
   C. Equal
   D. Either A. or B.; depends on the viscosity of the fluid

7. Equivalent length of a pipe fitting is____________________?

   A. Dependent on Reynolds number
   B. Independent of Reynolds number
   C. Dependent on the length of the pipe
   D. None of these

8. Boundary layer separation is characterised by one of the conditions given below, where ‘Re’ is the Reynolds number for the flow. Select the appropriate conditions ?

   A. Re <> 1, accelerating flow
   C. Re << 1, decelerating flow
   D. Re >>1, decelerating flow

9. Terminal velocity is_____________________?

   A. A constant velocity with no acceleration
   B. A fluctuating velocity
   C. Attained after moving one-half of total distance
   D. None of these

10. In Newton’s law range, the terminal velocity of a solid spherical particle falling through a stationary fluid mass varies as the ______________ of its diameter?

    A. Inverse
    B. Square root
    C. Second power
    D. First power