如图甲所示,理想变压器的原、副线圈的匝数比为3:1,保险丝的电阻为20Ω,熔断电流为2A,若原线圈接入如图乙所示的正弦交变电压,为了安全,滑动变阻器接入电路的阻值至少大于
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/15/4b5a24bb-ba1a-4aea-8b0a-e76a4704d17d.png?resizew=421)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/15/4b5a24bb-ba1a-4aea-8b0a-e76a4704d17d.png?resizew=421)
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更新时间:2018-10-09 19:08:29
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【推荐1】如图所示,理想变压器的
端所接的交变电压
,
、
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A.![]() ![]() |
B.变压器原、副线圈匝数比为4:1 |
C.减小电阻箱R连入电路的阻值,电压表![]() |
D.减小电阻箱R连入电路的阻值,电压表![]() |
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【推荐2】手机无线充电是近几年发展起来的新技术。如图甲电磁感应式无线充电原理与变压器类似,需要在手机和充电平台里各安装一个线圈,当充电基座上的送电线圈通入正弦式交变电流后,邻近的受电线圈中产生感应电流,为手机电池充电,假设在充电过程中手机放到基座上时,基座线圈产生的磁感线全部穿过受电线圈。已知受电线圈匝数为30匝,电阻不计,受电线圈内磁通量
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【推荐1】如图为理想变压器原线圈所接电源电压波形,原副线圈匝数之比
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