A pipe, 900 m long and 200 mm in diameter discharges water tothe atmosphere at a point 10 m below the inlet level. With an inletpressure of 40 kPa gauge, the flow rate is 40 litres/sec. At apoint half way between the pipe inlet and outlet, a new tapping ismade from which water is taken at a rate of 18 litres/sec. To whatvalue must the inlet pressure be raised in order to maintain thesame discharge rate from the end of the pipe? You may assume thatthe pipe remains full of water and that the average friction factoris not altered by making the new tapping. (ans.: 115.1 kN/m2)
