Head pressure in hydraulic calculations is expressed by multiplying vertical difference in feet by which constant?

Head pressure in hydraulic calculations is expressed by multiplying vertical difference in feet by which constant?

• A. 0.434 psi per foot
• B. 0.5 psi per foot
• C. 1.0 psi per foot
• D. 2.0 psi per foot

Answer: (A)

Head pressure comes from the weight of a vertical column of liquid, so you use P = γ h, where γ is the fluid’s weight density and h is the height of the column. For water, γ is about 62.4 pounds per cubic foot, and converting to psi per foot gives 62.4 lbf/ft^2 divided by 144 in^2/ft^2, which is 0.433 psi per foot. Rounding to three decimals gives 0.434 psi per foot. So a 1 ft rise adds about 0.434 psi, a 10 ft rise about 4.34 psi, and you’d use a different constant if the fluid isn’t water.

Head pressure comes from the weight of a vertical column of liquid, so you use P = γ h, where γ is the fluid’s weight density and h is the height of the column. For water, γ is about 62.4 pounds per cubic foot, and converting to psi per foot gives 62.4 lbf/ft^2 divided by 144 in^2/ft^2, which is 0.433 psi per foot. Rounding to three decimals gives 0.434 psi per foot. So a 1 ft rise adds about 0.434 psi, a 10 ft rise about 4.34 psi, and you’d use a different constant if the fluid isn’t water.