Water supplied to a house by a water main has a pressure of 2.7 × 105 N/m2 early on a summer day when neighborhood use is low. This pressure produces a flow of 21.5 L/min through a garden hose. Later in the day, pressure at the exit of the water main and entrance to the house drops, and a flow of only 7.8 L/min is obtained through the same hose.