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)
2 @, X2 \, s* H, W, Y1 t( X! Pif f=0 Xc is infinite, so capacitor block DC.
: V1 r( X6 p: S+ V9 H3 j+ ?" }( mfor 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
( q: P& f. M; }! ]为什么电容器阻断DC 而通AC?

0 D" B# q' |5 d4 m8 K
* o$ F5 T1 F% N' \I would like to ask a question, just for curiosity, if you do not mind.
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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！！！