出典:Wikipedia
出典:『Wikipedia』 (2011/06/24 15:14 UTC 版)
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ (the Greek letter rho). In some cases (for instance, in the United States oil and gas industry), density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight. Different materials usually have different densities, so density is an important concept regarding buoyancy, purity and packaging. Osmium and Iridium are the densest known metal elements at standard conditions for temperature and pressure but not the densest materials.
of something, to be thick and heavy
the fierce
the condition of low density
名詞の変化形:
|