Fluid mechanics is a branch of physics that studies the behavior of fluids, which can be either liquids or gases. It explores the principles and concepts that govern the motion and forces experienced by fluids. In this article, we will cover the basic properties of fluids, the classification of fluids into Newtonian and non-Newtonian categories, and the fundamental equations that describe fluid behavior.

Properties of Fluids:

Fluids have some unique properties that distinguish them from solids. One such property is the ability of fluids to flow and take the shape of their containers. This behavior arises due to the absence of shear strength in fluids, allowing them to deform under even the slightest applied force. Additionally, fluids can be compressible or incompressible, depending on whether changes in pressure significantly impact their volume.

Newtonian and Non-Newtonian Fluids:

Newtonian fluids exhibit a linear relationship between the applied shear stress and the resulting rate of deformation. Common examples of Newtonian fluids include water and most gases. On the other hand, non-Newtonian fluids do not adhere to this linear relationship and display more complex behaviors. Examples of non-Newtonian fluids are ketchup, toothpaste, and blood.

Fundamental Equations:

To analyze and predict the behavior of fluids, we employ the fundamental equations of fluid mechanics. The most important equation is the continuity equation, which states that mass is conserved in a fluid system. Other notable equations include Bernoulli's equation, which relates the pressure, velocity, and elevation of a fluid, and the Navier-Stokes equations, which describe the conservation of mass, momentum, and energy in a fluid.

By understanding the properties of fluids, distinguishing between Newtonian and non-Newtonian fluids, and utilizing the fundamental equations of fluid mechanics, we can begin to unravel the complexities of this fascinating field.