At a point A in a pipe line carrying water, the diameter is 1m, the pressure 98 kPa and the velocity 1m/s. At a point B, 2 m higher than A, the diameter is 0.5m and the pressure 20 kPa. The direction of flow would be
- A. A to B
- B. B to A
- C. Cannot be ascertained from data
- D. None of these
Answer: A. A to B
Explanation: Total Energy at A: $P/\gamma + v²/2g + z = 10 + 0.05 + 0 = 10.05$. At B: $V_B=4V_A=4$. $E_B = 2.04 + 0.81 + 2 = 4.85$. Fluid flows from high energy (A) to low energy (B).