Is absolute pressure higher than gauge pressure?

Is absolute pressure higher than gauge pressure?

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Yes, absolute pressure is higher than gauge pressure. Absolute pressure includes atmospheric pressure as a reference point, while gauge pressure is the pressure measured above atmospheric pressure. Here's a breakdown of these terms:

  1. Absolute Pressure:

    • Absolute pressure is the total pressure exerted by a fluid, including atmospheric pressure. It is measured relative to a perfect vacuum, where there is no pressure. In most pressure measurements, atmospheric pressure is used as the reference point.
    • Mathematically, absolute pressure (P_abs) is the sum of gauge pressure (P_gauge) and atmospheric pressure (P_atm):
    • Pabs = Pgauge + Patm​
  2. Gauge Pressure:

    • Gauge pressure is the pressure measured above atmospheric pressure. It does not take into account the atmospheric pressure at the location where the measurement is made.
    • Mathematically, gauge pressure (P_gauge) is the pressure measured by a pressure gauge minus atmospheric pressure:
    • Pgauge = Pabs - Patm​

In summary, if you have the absolute pressure, it includes the atmospheric pressure, and if you have the gauge pressure, it represents the pressure above atmospheric pressure. The absolute pressure will always be higher than the gauge pressure because it includes the atmospheric pressure component.