A smooth pipe of diameter 200mm carries water. The pressure in the pipe at Section S1 (elevation: 10m) is 50 kPa. At section S2 (elevation: 12m) the pressure is 20 kPa and velocity is 2m/sec. Density of water is 1000 kg/m³ and acceleration due to gravity is 9.8m/sec². Which of the following is true?
- A. Flow is from S1 to S2 and head loss is 0.53m
- B. Flow is from S2 to S1, and head loss is 0.53
- C. Flow is from S1 to S2 and head loss is 1.06m
- D. Flow is from S2 to S1 and head loss is 1.06m
Answer: C. Flow is from S1 to S2 and head loss is 1.06m
Explanation: Total Head H = P/\rho g + V²/2g + Z. H1 = 50000/9810 + V1^2/2g + 10. H2 = 20000/9810 + 2^2/19.6 + 12. Assume constant dia, V1=V2=2. H1 = 5.1 + 0.2 + 10 = 15.3m. H2 = 2.04 + 0.2 + 12 = 14.24m. H1 > H2, flow S1 to S2. Loss = 15.3 - 14.24 = 1.06m.