Dear guys, I got a common doubt regarding the pressure at the bottom of a open tank filled with water. 1) Assume a tank of 2m height, filled with water. So the hydrostatic pressure at the bottom of the tank will be 0.2 bar(rho*g*h). Wondering!! it is less then atmospheric pressure(1 bar). 2) So do i need to include the atmospheric pressure for my stress calculation, which is 4 times greater than the hydrostatic pressure.