Atmospheric tanks definition

We must introduce an additional definition of fluid pressure to explain the concept of atmospheric pressure and to discuss common methods for measuring pressures of fluids in tanks and pipes. Suppose a vertical column of fluid is /i(m) high and has a uniform cross-sectional area A(m ). Further suppose that the fluid has a density of p(kg/m ), and that a pressure Po(N/m ) is exerted on the upper surface of the column. (See Figure 3.4-2.) The pressure P of the fluid at the base of the column—called the hydrostatic pressure of the fluid—is, by definition, the force F exerted on the base divided by the base area A. F thus equals the force on the top surface plus the weight of the fluid in the column. It is not difficult to show that ... 

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