A village maintains a large tank with an open top, containing water
for emergencies. The water can drain from the tank through a hose
of diameter 6.70 cm. The hose ends with a nozzle of diameter 2.15
cm. A rubber stopper is inserted into the nozzle. The water level
in the tank is kept 7.50 m above the nozzle.
(a) Calculate the friction force exerted by the nozzle on the
(b) The stopper is removed. What mass of water flows from the
nozzle in 2.00 h?
(c) Calculate the gauge pressure of the flowing water in the hose
just behind the nozzle.