1 PSI is approximately how many feet of water?

1 PSI is approximately how many feet of water?

• A. 1.5
• B. 2.31
• C. 3.5
• D. 4.2

Answer: (B)

Pressure from a column of water comes from the weight of the water above, described by p = gamma × h, where gamma is the water’s specific weight. For freshwater, gamma is about 62.4 pounds-force per cubic foot (lbf/ft^3). To convert to psi, note that 1 psi equals 1 lbf per square inch, and there are 144 square inches in a square foot, so p(psi) = (gamma × h) / 144. Set p = 1 psi and solve for h: h = 1 × 144 / 62.4 ≈ 2.31 ft. So 1 psi is approximately 2.31 feet of water.

Pressure from a column of water comes from the weight of the water above, described by p = gamma × h, where gamma is the water’s specific weight. For freshwater, gamma is about 62.4 pounds-force per cubic foot (lbf/ft^3). To convert to psi, note that 1 psi equals 1 lbf per square inch, and there are 144 square inches in a square foot, so p(psi) = (gamma × h) / 144.

Set p = 1 psi and solve for h:

h = 1 × 144 / 62.4 ≈ 2.31 ft.

So 1 psi is approximately 2.31 feet of water.