If a gauge reads 175 psi and it is located 45 feet below the connection point, what is its true reading?

When assessing the pressure reading on a gauge located at a specific depth below a connection point, it is essential to account for the hydrostatic pressure exerted by the column of fluid above the gauge. The pressure gauge reads the pressure relative to the atmosphere (gauge pressure), and this reading can be influenced by the height of the fluid column above it.

To find the true pressure reading (absolute pressure), you need to calculate the additional pressure exerted by the water column. The formula to find the hydrostatic pressure is:

Hydrostatic pressure (psi) = Depth (feet) × 0.433 psi/foot

In this case, the depth is 45 feet. So, the hydrostatic pressure would be:

Hydrostatic pressure = 45 feet × 0.433 psi/foot = 19.485 psi

Since the gauge reads 175 psi, the true pressure reading is calculated by subtracting the hydrostatic pressure from the gauge reading:

True pressure = Gauge reading - Hydrostatic pressure

True pressure = 175 psi - 19.485 psi ≈ 155.515 psi

Rounding to one decimal place, this results in a true reading of 155.5 psi. Therefore, the correct answer reflects