Example

lA water tower is a
familiar sight in many
towns. The purpose of such a tower
is to provide storage
capacity and to provide sufficient
pressure in the pipes that deliver
the water to customers.
The drawing shows a spherical
reservoir that contains
5.25 x 105 kg of water when full. The reservoir is vented to the atmosphere at the top. For a full reservoir, find the gauge pressure that the water has at the faucet in

lhouse A

lhouse B.

lIgnore the diameter
of the delivery pipes.

Apply P = P0 + rgh

Find
house A’s pressure first using h = 15 m

Then
find house B’s pressure using h = 15-7.3 = 7.7 m