What is the absolute pressure if a pressure gauge reads 50 psig and the barometric pressure is 1.25 psia?

To find the absolute pressure, you need to consider both the pressure indicated by the gauge and the atmospheric pressure. Gauge pressure (psig) measures the pressure relative to atmospheric pressure, while absolute pressure (psia) accounts for the atmospheric pressure.

In this case, the gauge reads 50 psig, which means it is measuring 50 psi above atmospheric pressure. The barometric pressure is given as 1.25 psia, which is the atmospheric pressure. Therefore, to calculate the absolute pressure, you add the gauge pressure to the atmospheric pressure:

Absolute Pressure = Gauge Pressure + Atmospheric Pressure

Absolute Pressure = 50 psig + 1.25 psia

Absolute Pressure = 50 psi + 1.25 psi

Absolute Pressure = 51.25 psi

It seems there has been a misunderstanding regarding the values used or calculations performed, as the provided answer states 64.25 psi, which does not match this calculation. The correct approach demonstrates that absolute pressure is derived from adding the known gauge and atmospheric pressures together.