Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around________________?

Related Mcqs:

1. A fluid (μ/ρ) = 0.01 cm2/sec is moving at critical flow condition (NRe = 2100) through a pipe of dia 3 cms. Velocity of flow is _______________ cm/sec?

   A. 7
   B. 700
   C. 7000
   D. 630

2. A pipe of I.D. 4 m is bifurcated into two pipes of I.D. 2 m each. If the average velocity of water flowing through the main pipe is 5 m/sec, the average velocity through the bifurcated pipes is__________________?

   A. 20 m/sec
   B. 10 m/sec
   C. 5 √2 m/sec
   D. 5 m/sec

3. A Rotameter through which air at room temperature and atmospheric pressure is flowing gives a certain reading for a flow rate of 100 cc/sec. If helium (molecular weight 4) is used and Rotameter shows the same reading, the flow rate (cc/sec) is__________________?

   A. 26
   B. 42
   C. 269
   D. 325

4. A pipe has a porous section of length L as shown in the figure. Velocity at the start of this section of V0. If fluid leaks into the pipe through the porous section at a volumetric rate per unit area q(x/L)2, what will be axial velocity in the pipe at any „x‟? Assume incompressible one dimensional flow i.e., no gradients in the radial direction ?

   A. VX = V0 + q (x3/L2D)
   B. VX = V0 + ⅓q (x3/L2)
   C. VX = V0 + 2q (x2/LD)
   D. VX = V0 + (4/3) q (x3/L2D)

5. The pressure drop per unit length of pipe incurred by a fluid ‘X’ flowing through pipe is Δp. If another fluid ‘Y’ having both the specific gravity & density just double of that of fluid ‘X’, flows through the same pipe at the same flow rate/average velocity, then the pressure drop in this case will be__________________?

   A. Δp
   B. 2Δp
   C. Δp2
   D. Δp/2

6. What is the ratio of the velocity at the axis of the pipe to the mean velocity of flow in case of pipe flow under viscous condition ?

   A. 0.5
   B. 0.67
   C. 1
   D. 2

7. In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of___________________?

   A. Relative roughness
   B. Absolute roughness
   C. Friction co-efficient for flows at equal Reynold number
   D. All A., B. & C.

8. Reynolds number for water flow through a tube of I.D. 5 cm is 1500. If a liquid of 5 centipoise viscosity and 0.8 specific gravity flows in the same pipe at the same velocity, then the pressure drop will______________________?

   A. Increase
   B. Decrease
   C. Remain same
   D. Data insufficient to predict pressure drop

9. The velocity profile exhibited by laminar flow of Newtonian fluids is such that the velocity distribution w.r.t. radius of the circular pipe is a/an ______________ with the apex at the centre line of the pipe?

   A. Hyperbola
   B. Parabola
   C. Semi-circle
   D. Semi-ellipse

10. For turbulent flow in smooth circular pipe, the velocity distribution is a function of the distance ‘d’ measured from the wall of the pipe and the friction velocity ‘v’, and it follows a _____________ relationship?

    A. Logarithmic
    B. Linear
    C. Hyperbolic
    D. Parabolic