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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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