出典:Wiktionary
出典:Wikipedia
出典:『Wikipedia』 (2011/07/05 18:00 UTC 版)
Energy density is a term used for the amount of energy stored in a given system or region of space per unit volume. Often only the useful or extractable energy is quantified, which is to say that chemically inaccessible energy such as rest mass energy is ignored. Quantified energy is energy that has some sort of, as the name suggests, quantified magnitude with related units.