Fluid Mechanics — Quiz 5

Questions in this quiz (10)

1. The kinematic viscosity of a fluid is $$4\times10^{-5}\ \text{m}^2/\text{s}$$ in a $$0.08\ \text{m}$$ diameter pipe. If the velocity of the flow is $$1.2\ \text{m/s}$$, the type of flow is most nearly:

   • Laminar flow
   • Transitional flow
   • Fully turbulent flow
   • Cannot be determined

2. A $$1.5\text{-ft}$$ diameter circular tube has laminar flow with a maximum velocity of $$4\ \text{m/s}$$. The velocity $$\left(\text{m/s}\right)$$ of the flow close to the periphery of the tube is most nearly:

   • 0
   • 2
   • 4
   • 3.1

3. A $$1.5\text{-ft}$$ diameter circular tube has laminar flow with a maximum velocity of $$4\ \text{m/s}$$. The velocity $$\left(\text{m/s}\right)$$ of the flow at the centerline of the tube is most nearly:

   • 2
   • 4
   • 0
   • 3.1

4. The average velocity of a fully turbulent flow is $$6\ \text{m/s}$$. The maximum velocity $$\left(\text{m/s}\right)$$ of the flow is most nearly:

   • 7.1
   • 6.0
   • 8.4
   • 9.0

5. The hydraulic diameter of a noncircular conduit is $$24\ \text{in}$$. The hydraulic radius of that conduit if it has full flow is most nearly:

   • 3 in
   • 6 in
   • 12 in
   • 24 in

6. A fluid is flowing at $$2\ \text{m/s}$$ in a $$0.03\ \text{m}$$ diameter conduit. The length of the conduit is $$40\ \text{m}$$. If the Moody friction factor is $$0.025$$, the head loss of the flow is most nearly:

   • 4.52 m
   • 6.79 m
   • 3.41 m
   • 8.12 m

7. The Reynolds number of a flow through a pipe is $$150000$$. The relative roughness of the pipe is $$0.006$$. The friction factor of the pipe flow is most nearly:

   • 0.018
   • 0.028
   • 0.036
   • 0.052

8. The Reynolds Number of a flow is $$5$$. The drag coefficient of a spherical object inside the flow is most nearly:

   • 4.8
   • 6.2
   • 9.6
   • 12

9. A spherical object is placed inside a water flow with $$Re=6$$ and velocity of $$1.2\ \text{m/s}$$. The projected area of the spherical object perpendicular to the flow is $$0.015\ \text{m}^2$$. Determine the drag force exerted on the spherical body most nearly:

   • 9 N
   • 12 N
   • 16 N
   • 21 N

10. What is most nearly the drag coefficient for a flat plate placed parallel to the flow with $$Re=80000$$?

    • 0.0047
    • 0.047
    • 0.47
    • 4.7