The major loss of energy in long pipes is due to_______________?

Related Mcqs:

1. The horse power transmitted through a pipe is maximum when the ratio of loss of head due to friction and total head supplied is________________?

   A. 1/3
   B. 1/4
   C. 1/2
   D. 2/3

2. The value of friction factor ‘f’ for smooth pipes for Reynolds number 106 is approximately equal to________________?

   A. 0.1
   B. 0.01
   C. 0.001
   D. 0.0001

3. Two pipes of same length and diameters d and 2d respectively are connected in series. The diameter of an equivalent pipe of same length is________________?

   A. less than d
   B. between d and 1.5 d
   C. between 1.5 d and 2d
   D. greater than 2d

4. If the elevation of hydraulic grade line at the junction of three pipes is above the elevation of reservoirs B and C and below reservoir A, then the direction of flow will be___________________?

   A. from reservoir A to reservoirs B and C
   B. from reservoir B to reservoirs C and A
   C. from reservoir C to reservoirs A and B
   D. unpredictable

5. For laminar flow in circular pipes, the Darcy’s friction factor f is equal to_________________?

   A. 16/Re
   B. 32/ Re
   C. 64/ Re
   D. none of the above where R,, is Reynolds number

6. The ratio of average velocity to maximum velocity for steady laminar flow in circular pipes is_______________?

   A. 1/2
   B. 2/3
   C. 3/2
   D. 2

7. The total pressure on a plane surface inclined at an angle 9 with the horizontal is equal to_______________?

   A. PA
   B. pA sin 9
   C. pA cos 9
   D. pA tan 9

   where p is pressure intensity at centroid of area and A is area of plane surface

8. An open cubical tank of 2 m side is filled with water. If the tank is rotated with an acceleration such that half of the water spills out, then the acceleration is equal to_______________?

   A. g/3
   B. g/2
   C. 2g/3
   D. g

9. The correct relationship among displacement thickness d, momentum thickness m and energy thickness e is_________________?

   A. d > m > e
   B. d > e > m
   C. e > m > d
   D. e > d > m

10. If velocity is zero over l/3rd of a cross-section and is uniform over remaining 2/3rd of the cross-section, then the correction factor for kinetic energy is__________________?

    A. 4/3
    B. 3/2
    C. 9/4
    D. 27/8