Pressure at a point inside a liquid
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To Drive the pressure at a point inside a liquid :

Suppose a vertical column of still liquid in the form of a rectangular block, its top at the liquid's surface and it's base area ( A ) and the height ( H ) which is the depth of this point .

Pressure difference between a point at its base and another at its top delta P

Delta P = weight of column /base area = mg/A = rVg/A = rhAg/A = rhg   N/m^2 

 

Factors affecting the pressure difference at a point inside a liquid :
Delta P a r  at constant h
Delta P a h  at constant  r    if it's in a certain place.
it also proportional to the value of ( G ) as ( G ) changes from place to another.

NB :
 ( 1 ) The pressure at a point inside a liquid is independent on 

i ) direction ( acts equally in all directions )
ii ) Base area
iii ) Shape of container

 ( 2 ) The pressure difference between two point inside a liquid Delta P = rhg
Where r ( density of liquid), h ( vertical height between the two points or thickness of liquid's layer )

( 3 ) The total ( absolute ) pressure at a point inside liquid Pabs = Pa + Delta P = Pa + rhg
Where Pa is the atmospheric pressure.