连接电路时,为什么要将开关断开?合上开关前,为什么要将滑动变阻器的滑片置于使接入电路的电阻值最大的位置
人气:168 ℃ 时间:2019-08-30 13:54:50
解答
安全规定
连接电路时将开关断开防止短路烧坏电源
将滑动变阻器的滑片置于使接入电路的电阻值最大的位置 防止电流过大烧坏滑动变阻器
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