1. SOLIDS

2. Crystal Structure  Atoms of a solid arrange in regular geometric shapes  Certain solids atoms repeat in shapes at the atomic level, which produces geometric shapes at the visible level  Bug rock??

3. Density  A measure of how tightly a material is packed together  Density = ___Mass___ Volume  If something is very dense, it has a lot of mass in a relatively small volume  Density of water is 1 g/cm 3  Other examples  Gold 19 g/cm 3, lead 11.3 g/cm 3, platinum 21.4 g/cm 3, mercury 13.6 g/cm 3, Steel 7.8 g/cm 3, Earth 5.5 g/cm 3

4. Elasticity  The property of a body that by which if it experiences a change in shape it will readily return to its original shape Ex. Baseball, Steel, springs The amount of deformation is proportional to the amount of force ex. Double the force causing the stretch, the amount of stretch will also be doubled  Inelastic - once it is deformed, it stays deformed ex. Clay, mashed potatoes, silly puddy  Equilibrium Position – the position of a an object when no force is being appled to stretch or compress it  Spring Constant – Value for every material that indicates how elastic it is. Expressed in N/m

5. Elastic Limit  A material can only be stretched so far before it becomes permanent  Elastic limit --- the point at which permanent distortion occurs  Examples?? 

6. Compression & Tension  Elastic materials will can often be compressed or stretched  Compression  A type of stress in which the material is pulled together  Tension  A type of stress in which the material is pulled apart

7. Compression & Tension at same time