Like solids, the molecules in a liquid are bonded to neighboring molecules, but possess many fewer of these bonds. (Shearing forces are forces applied tangentially to a surface, as described in Static Equilibrium and Elasticity.) Characteristics of FluidsĬonsidered to be fluids because they yield to shearing forces, whereas solids resist them. Even a large force produces only small displacements in the atoms or molecules of the lattice, and the solid maintains its shape. The structure of this three-dimensional lattice is represented as molecules connected by rigid bonds (modeled as stiff springs), which allow limited freedom for movement. In some cases, the force between molecules can cause the molecules to organize into a lattice as shown in Figure 14.2. Although true solids are not incompressible, it nevertheless requires a large force to change the shape of a solid. Solids will take a form determined by the nature of these forces between the molecules.
The atoms or molecules in a solid are in close proximity to each other, and there is a significant force between these molecules. Solids are rigid and have specific shapes and definite volumes. We will look at each of these phases in detail in this section. Matter most commonly exists as a solid, liquid, or gas these states are known as the three common phases of matter.
Distinguish between compressible and incompressible materials.Describe the characteristics of the phases of matter at the molecular or atomic level.By the end of this section, you will be able to: