Two reservoirs whose difference of level is 13,5m are connected by a pipe ABC, whose highest point B is 1,5m below the level in the upper reservoir A . The portion AB has a diameter of 200 mm and the portion BC a diameter of 150 mm , the coefficient of friction for -each being 0,005 . The total length of the pipe is 3 km . Find the maximum allowable length of the portion AB if the pressure at B is not to be more than 3 m below atmospheric pressure. Neglect the velocity head in the pipe and the shock losses.
( 2034 m )