What is the static head pressure of a 20' column of water?

What is the static head pressure of a 20' column of water?

• A. 10
• B. 5
• C. 20
• D. 15

Answer: (A)

Static head pressure is the pressure produced by the weight of a fluid column. It equals the fluid’s weight density times the height of the column. For water, the weight density is about 62.4 lb/ft^3. A 20-ft column yields 62.4 × 20 = 1,248 lb/ft^2. Convert to psi by dividing by 144 (in^2 per ft^2): 1,248 / 144 ≈ 8.7 psi. In many practical problems this is rounded to about 9 or 10 psi, so the closest option is 10 psi. The other values (5, 15, 20 psi) are farther from the calculated pressure.

Static head pressure is the pressure produced by the weight of a fluid column. It equals the fluid’s weight density times the height of the column. For water, the weight density is about 62.4 lb/ft^3. A 20-ft column yields 62.4 × 20 = 1,248 lb/ft^2. Convert to psi by dividing by 144 (in^2 per ft^2): 1,248 / 144 ≈ 8.7 psi. In many practical problems this is rounded to about 9 or 10 psi, so the closest option is 10 psi. The other values (5, 15, 20 psi) are farther from the calculated pressure.