Pressure (symbol: P or p) is the ratio of force to the area over which that force is distributed.

Pressure is force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure (also spelled gage pressure)^[a] is the pressure relative to the local atmospheric or ambient pressure. Pressure is measured in any unit of force divided by any unit of area. The SI unit of pressure is the newton per square metre, which is called the pascal (Pa) after the seventeenth-century philosopher and scientist Blaise Pascal. A pressure of 1 Pa is small; it approximately equals the pressure exerted by a dollar bill resting flat on a table. Everyday pressures are often stated in kilopascals (1 kPa = 1000 Pa).

 

뚜껑이 없는 원통형의 용기에 물이 차있다고 하면

Pt = 대기압 + 물에 작용하는 중력에 의한 압력(밀도 x 중력가속도 x 높이)

이지 않습니까? 위에 빨간색 줄도 그런 의미인 것 같은데요.

 

그런데요....대기압이 101.325 kpa 를 어떻게 나타내는지 갑자기 너무 궁금합니다.

대기 중에 Surface 나 Object가 없는데 그 대기압력은 어떻게 존재하는지요...

기체들만 있을 것으로 생각되는데요.

 

알려주세요...ㅎ