SSC JE Civil Engineering 23-Mar-2021 Shift 1 Paper

Concept:
Hydrostatic Law:
The pressure at any point in a fluid at rest is obtained by the Hydrostatic Law which states that In an incompressible static fluid column, the rate of increase of pressure in a vertically downward direction must be equal to the specific weight of the fluid at that point.​​
$\frac{\mathrm{dP}}{\mathrm{dh}}=\mathrm{\rho }\mathrm{g}$
$\int \mathrm{dP}=\mathrm{\rho }\mathit{g}\int \mathrm{dh}$
$\mathrm{P}=\mathrm{\rho }\mathrm{gh}$
where P = pressure above atmospheric pressure and h = height of the point from the free surface.