{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "# Introduction\n", "\n", "There are several concepts that need to be introduced before we embark on a course in fluid mechanics. For example, what exactly is a fluid?\n", "\n", "Herein we will provide definitions of:\n", "\n", "- Solids, liquids and gases\n", "- Types of forces relevant to fluid mechanics\n", "- Methods of describing fluid behaviour\n", "- Fluid Properties\n", "- Flow Properties\n", "\n", "Concepts such as pressure will be covered in detail in a separate notebook.\n", "\n", "## Learning Outcomes\n", "\n", "\n", "## Solid Liquid and Gases\n", "\n", "Of the three states of matter — solid, liquid and gas — the latter two are classified as fluids. What defines a solid? How are fluids different? \n", "\n", "Unlike solids, fluids flow!\n", "\n", "\n", "### Solids\n", "\n", "A solid is comprised of densely packed molecules, often in precise crystal structures such as found in metals or when water is frozen into ice. In Solid Mechanics you will have learned about stress, strain and elastic and plastic deformation. The video below illustrates how the densely packed atoms of a solid respond elastically to longidutional, torsion amd shear loads. \n", "\n", "