Page 13 - FLUID MECHANICS EBOOK FINAL (2)

FLUID MECHANICS

A fluid is a substance which can deforms continuously when being subjected to

shear stress at any magnitude, however small they may be. Conversely, if a fluid is

at rest, there can be no shearing forces acting and, therefore, all forces in the fluid

must be perpendicular to the planes upon which they act. When the fluid is in
motion shear stress are developed if the particles of the fluid move relative to each

other. When this happens adjacent particles have different velocities, causing the

shape of the fluid to become distorted. Refer Figure below for the illustration.

Figure 1.1 : Illustration Of Shear Force Acting at Fluid

1.1.2 Describe the Characteristics of Fluid

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