1. The friction factor for turbulent flow in a hydraulically smooth pipe is?

2.  Consider two pipes of the same length and diameter through which water is passed at the same velocity. The friction factor for rough pipe if f1 and that for smooth pipe is f2. Pick out the correct statement.
a. f1 =f2 

b.f1 >f2 

c.f1

d.insufficient data

3.  An imaginary curve in a mass of flowing fluid so that at every point on the curve the net-velocity vector is tangent to that imaginary curve.

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