Water runs downhill. This is the basis for how the height of water towers provides pressure to your tap water. In ancient times, this was the basis for how fountains worked without motors. Each foot of height of a water tower provides 0.43 pounds per square inch (PSI).
Instructions
1. Imagine a column demarcation inside the water tower that has a cross section of one foot by one foot, and a height equal to the height of the tower. The weight of the water outside of this demarcation doesn't contribute to the net upward or downward pressure on the water in the column. Therefore, the water inside the demarcation can be considered in isolation.
2. Weigh the water in the column. A cubic foot of water weighs 62.4 pounds. So each foot of height adds 62.4 pounds of downward force.
3. Multiply the height in feet by 62.4 to get pounds per square foot.
4. Divide by 144 to get pounds per square inch (PSI), i.e. multiply the height by 0.43 to get the pressure in PSI. This will be the pressure that the tower exerts. If h is the height in feet, the formula is Water Pressure = 0.43h PSI.
Tags: foot height, pounds square, height feet, height water, pounds square inch