The depth ‘d’ below the free surface at which the point velocity is equal to the average velocity of flow for a uniform laminar flow with a free surface, will be_________________?

Related Mcqs:

1. A vertical rectangular plane surface is submerged in water such that its top and bottom surfaces are 1.5 m and 6.0 m res-pectively below the free surface. The position of center of pressure below the free surface will be at a distance of________________?

   A. 3.75 m
   B. 4.0 m
   C. 4.2m
   D. 4.5m

2. 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

3. The distance y from pipe boundary, at which the point velocity is equal to average velocity for turbulent flow, is________________?

   A. 0.223 R
   B. 0.423 R
   C. 0.577 R
   D. 0.707 R

   where R is radius of pipe

4. For a sphere of radius 15 cm moving with a uniform velocity of 2 m/sec through a liquid of specific gravity 0.9 and dynamic viscosity 0.8 poise, the Reynolds number will be_________________?

   A. 300
   B. 337.5
   C. 600
   D. 675

5. A fluid of kinematic viscosity 0.4 cm2/sec flows through a 8 cm diameter pipe. The maximum velocity for laminar flow will be__________________?

   A. less than 1 m/sec
   B. 1 m/sec
   C. 1.5 m/sec
   D. 2 m/sec

6. The velocity distribution for laminar flow through a circular tube__________________?

   A. is constant over the cross-section
   B. varies linearly from zero at walls to maximum at centre
   C. varies parabolically with maximum at the centre
   D. none of the above

7. 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

8. In a two dimensional incompressible steady flow around an airfoil, the stream lines are 2 cm apart at a great distance from the airfoil, where the velocity is 30 m/sec. The velocity near the airfoil, where the stream lines are 1.5 cm apart, is_________________?

   A. 22.5 m/sec
   B. 33 m/sec
   C. 40 m/sec
   D. 90 m/sec

9. If the velocity is zero over half of the cross-sectional area and is uniform over the remaining half, then the momentum correction factor is_______________?

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

10. When the velocity distribution is uniform over the cross-section, the correction factor for momentum is__________________?

    A. 0
    B. 1
    C. 4/3
    D. 2