Negative pressure & Hydrostatic paradox

[Deathfish]

2 parts:

1. What does it mean if you get a negative gauge pressure value when calculating from manometer containing compound liquid? When calculating absolute pressure how does atmospheric pressure affect this negative pressure ie. atmospheric pressure opposes the direction of force?

2. Someone explain to me the hydrostatic paradox in simple terms for short answer question.

 

[Curl]

1) It means that you are measuring a pressure below the reference pressure.

2) It's called Pascal's law. http://en.wikipedia.org/wiki/Pascal's_law