Solid
- In Geometry, a solid is a three-dimensional figure. See Solid geometry.
- In jewelry, a solid gold piece is the alternative to gold-filled or gold-plated jewelry. The term can also apply to other precious metals, such as solid silver.
- In Woodworking, a solid piece of wood is the alternative to using one type of wood for the structure with a different veneer wood used on the surface. The term can also be used to describe the non-hollow version of wooden objects, such as doors.
A solid is a phase of Matter characterized by resistance to Deformation and to changes of Volume.
At the microscopic scale, a solid has these properties:
- The atoms or molecules that comprise the solid are packed close together.
- These constituent elements have fixed positions in space relative to each other. This accounts for the solid's rigidity.
- If sufficient force is applied, either of these properties can be violated, causing permanent deformation.
- Because any solid has some Thermal energy, its atoms vibrate. However, this movement is very small and very rapid, and cannot be observed under ordinary conditions.
The branch of Physics that deals with solids is called Solid-state physics, and is a type of Condensed matter physics. Materials science is primarily concerned with properties of solids such as strength and phase transformations. It overlaps strongly with solid state physics. Solid-state chemistry overlaps both of these fields, but is especially concerned with the synthesis of novel materials.
The lightest known solid is man-made and is called Aerogel. The lightest aerogel produced has a density of 1.9 Mg per cm3 or 1.9 kg/m3 (526.3 times lighter than water).