Question

For laminar flow through a long pipe, the pressure drop per unit length increases

• A. in linear proportion to the cross-sectional area
• B. in proportion to the diameter of the pipe
• C. in inverse proportion to the cross-sectional area
• D. in inverse proportional to the square of cross-sectional area

Answer 1

The correct option is C in inverse proportion to the cross-sectional area

Loss in pressure in due to head loss due to friction.

$P_1-P_2=\frac{32\mu \overline{u}L}{D^2}$