The meaning of volt

伏特是国际单位制中电压的单位，符号V。 在一根均匀的、温度和宽度恒定的导线上假如有一安培电流流动，那么导线的电阻在一定的距离内可以将电能转化为热能。这个距离之间的电压差就被定义为一伏特： 图片参考：upload.wikimedia/math/0/2/2/0227a9f97f16bc681b905f117f0736e6 在国际单位制中安培是基本电学单位，伏特的SI定义是以安培和力学单位瓦特导出的。 依据国际单位制的基本电学单位安培，伏特定义为:"在载荷1A恒定电流的导线上，当两点之间导线上的功率耗散为1W(1W=1 J/S)时，这两点之间的电位差"。 此单位是以发明电源的义大利物理学家亚历山德罗·伏特的名字命名的。 The volt (symbol: V) is the SI derived unit of electric potential difference or electromotive force [1]. It is named in honor of the Italian physicist Alessandro Volta (1745–1827)

who invented the voltaic pile

the first chemical battery. The volt is defined as the potential difference across a conductor when a current of one ampere dissipates one watt of power. Hence

it is the base SI representation m2 · kg · s-3 · A-1

which can be equally represented as one joule of energy per coulomb of charge

J/C. 图片参考：content.wers/main/content/wp/en/math/c/e/7/ce7a54a5296725cb897f775a377e47ec . Since 1990 the volt is maintained internationally for practical measurement using the Josephson effect

where a conventional value is used for the Josephson constant

fixed by the 18th General Conference on Weights and Measures as K{J-90} = 0.4835979 GHz/?V.

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