gauge pressure

physics

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June 29, 2026

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Gauge pressure is the pressure at a point in a fluid that is above atmospheric pressure. It is measured by instruments called pressure gauges, which determine the difference between two pressures.12

For example, a tire-pressure gauge indicates the pressure inside the tire in excess of atmospheric pressure. If the gauge reads 30 pounds per square inch, the absolute pressure inside the tire, including atmospheric pressure, is 45 pounds per square inch. Pressures below atmospheric are considered negative gauge pressures, indicating a partial vacuum.3

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pressure gauge
…pressures, is known as the gauge pressure. If the lower of the pressures is the pressure of the atmosphere, the total, or absolute, pressure is the sum of the gauge and atmospheric pressures.
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…pressures, is known as the gauge pressure. If the lower of the pressures is the pressure of the atmosphere, the total, or absolute, pressure is the sum of the gauge and atmospheric pressures.
Read More