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FLUID MECHANICS


               1.1.3          Compare the Characteristics of Liquid, Gas and Solid































                           Figure 1.2 : Comparison of the Characteristics between Liquid, Gas and Solid




               1.2   TYPES OF PRESSURE


                              Pressure is defined as force per unit area. It is usually more convenient to

                       use pressure rather than force to describe the influences upon fluid behavior. The

                       standard unit for pressure is the Pascal, which is a Newton per square meter.


                       For an object sitting on a surface, the force pressing on the surface is the weight of

                       the object, but in different orientations it might have a different area in contact with
                       the surface and therefore exert a different pressure.
















                       Pressure in a fluid can be seen to be a measure of energy per unit volume by means

                       of the definition of work. This energy is related to other forms of fluid energy by the
                       Bernoulli equation(chapter 3).




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