电工面试问题之七

爱城电工

为什么电容器阻断DC 而通AC?

牛肉粉丝

Xc=1/(2Pifc)
- I2 M, D, L( Q, [' L: V4 X; }8 N" yif f=0 Xc is infinite, so capacitor block DC.
$ P9 Y8 @- x7 ofor AC, frequence is 60Hz(in north american), so Xc is a specific value. as a result , it can conduct AC.

MrElectrician

原帖由 爱城电工 于 2009-1-12 19:16 发表
* \) s( s. f; e& C/ L为什么电容器阻断DC 而通AC?

- j5 z! N1 z2 B5 z2 m$ ^7 w' K, D/ l
1 }4 F; d% X3 h5 WI would like to ask a question, just for curiosity, if you do not mind.

Is that a real question during your interview for an electrician job?

shenyang-china

Ha Ha, I think it is a joke. If it  was real, Lz must have lost his job.

wolfgan

电容器你可以想象成为一个容器，是用来装电子的，但是电子是不可以直接从这个容器里跑出去的，他是靠电压的变化或电流的变化来改变两级的电量而形成电流，所以对直流起到了一个不通的，而交流可以通过！！！