出典:Wiktionary
出典:『Wiktionary』 (2008/07/03 14:08 UTC 版)
physical constant (複数形 physical constants)
Contrasted with a mathematical constant by a physical measurement.
出典:Wikipedia
出典:『Wikipedia』 (2011/06/03 10:41 UTC 版)
A physical constant is a physical quantity that is generally believed to be both universal in nature and constant in time. It can be contrasted with a mathematical constant, which is a fixed numerical value but does not directly involve any physical measurement.