What would be the pressure measured in psia if the gauge reads 340 psig at sea level?

To determine the absolute pressure in psia from a gauge pressure reading, you must account for atmospheric pressure. Gauge pressure, measured in psig, indicates the pressure relative to atmospheric pressure; it reflects how much pressure is above ambient conditions. At sea level, the average atmospheric pressure is approximately 14.7 psi.

In this scenario, the gauge reads 340 psig. To convert this to absolute pressure (psia), you add the atmospheric pressure to the gauge pressure:

[

\text{Absolute Pressure (psia)} = \text{Gauge Pressure (psig)} + \text{Atmospheric Pressure (psi)}

]

Calculating this gives:

[

\text{Absolute Pressure (psia)} = 340 \text{ psig} + 14.7 \text{ psi} = 354.7 \text{ psia}

]

This calculation accurately reflects the principle of converting gauge pressure to absolute pressure by adding the local atmospheric pressure, thus confirming that the correct answer is indeed 354.7 psia.