上麵已講過,日本不是分兩種電壓,而是東西兩地電的周波數不同。關於電的周波數在初中物理應學過。

來源: jdy 於 2015-12-15 20:12:47 [舊帖] [給我悄悄話] 本文已被閱讀：次

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