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- Pressure $p$ in the Bernoulli equation 2 answers
In Bernoulli's equation the pressure plus kinetic and potential energy is constant. But what is this pressure term, physically? Is it the pressure of the fluid on the walls of the container or is it the pressure exerted on the fluid by the surroundings (air/liquid as air is also fluid). Because these two types of pressure are entirely different. In torricelli's law it is the pressure exerted by the atmosphere on the fluid and in venturimeter it is the pressure that the fluid under consideration exerts on the tube. I want some logical answers so that I could easily see what this pressure is physically - the formulas I know.