How does a pressure gauge measure absolute pressure?
A. It measures the difference between the pressure being measured and a reference pressure
B. It measures the pressure being measured with respect to a perfect vacuum
C. It measures the pressure being measured with respect to atmospheric pressure
D. It cannot measure absolute pressure
Answer:B
How does a pressure gauge measure absolute pressure?
A. It measures the difference between the pressure being measured and a reference pressure B. It measures the pressure being measured with respect to a perfect vacuum C. It measures the pressure being measured with respect to atmospheric pressure D. It cannot measure absolute pressure
Explanation: Absolute pressure is the pressure of a fluid with respect to a perfect vacuum. A pressure gauge that measures absolute pressure has a sealed reference chamber inside, which is evacuated to create a perfect vacuum. The pressure being measured is then applied to the other side of the gauge diaphragm or bourdon tube, and the difference in pressure between the vacuum and the process is indicated on the gauge face.