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        什么叫电流?

        发布日期: 2012-05-25 信息来源: 系统管理员

        答:水在水管里流动叫水流,电在电线里流动叫电流。也就是电能沿着传电的物体朝着一定方向有规律的流动,是看不见,摸不着的。电流速度每秒30万公里。

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