If you compare absolute pressure to gauge pressure,
A. gauge pressure would always be lower.
B. the two pressures would be the same.
C. gauge pressure would always be higher.
D. gauge pressure might be higher or lower.
The correct answer and explanation is:
The correct answer is D. Gauge pressure might be higher or lower.
Explanation:
Pressure is typically measured in two ways: absolute pressure and gauge pressure. Absolute pressure refers to the total pressure exerted by a system, including atmospheric pressure. It is the actual pressure measured relative to a complete vacuum. On the other hand, gauge pressure is the difference between the absolute pressure and atmospheric pressure. Essentially, gauge pressure indicates how much the pressure is above or below the local atmospheric pressure.
- Absolute Pressure:
This is the total pressure exerted on a system, including the atmospheric pressure. It is always a positive value because it includes the pressure from the atmosphere as well as any additional pressure applied. - Gauge Pressure:
Gauge pressure measures how much pressure is exerted above or below atmospheric pressure. If the pressure is higher than atmospheric pressure, the gauge pressure will be positive. If the pressure is lower than atmospheric pressure, the gauge pressure will be negative, indicating a vacuum.
Thus, gauge pressure can be both higher or lower than absolute pressure. If the system’s pressure is above atmospheric pressure, the gauge pressure will be positive, and it will be lower when the system is in a vacuum or below atmospheric pressure.
In some cases, gauge pressure might be zero when the absolute pressure is equal to atmospheric pressure. This means there is no excess pressure in the system, and it’s at the same level as the surrounding environment.
Therefore, the relationship between gauge pressure and absolute pressure can vary depending on the conditions, so gauge pressure might be higher or lower than absolute pressure.