A fire hose has a length of 100 feet , is 4 inches in diameter and has a roughness of 1/4inch. The fire hose leads into a nozzle that narrows from 4 inches diameter at the inlet to 2 inches at the outlet. The pressure at the nozzle inlet is 75 lbf/in^2 and atmospheric pressure (14.7 lbf/in^2) at the outlet.
What is the velocity of water at the nozzle outlet? Assume viscous effects are negligible and the elevation change between the nozzle inlet and outlet is negligible.