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)
! N9 o$ m8 v3 ~' p/ m, W+ `/ Pif f=0 Xc is infinite, so capacitor block DC.
% Q4 q4 H1 L8 p: N+ B) Kfor 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
' L- h4 v  z5 i+ w' x% R: h为什么电容器阻断DC 而通AC?

+ t3 F/ U) o& t6 q
0 r+ j. D" ]2 Z% U; SI would like to ask a question, just for curiosity, if you do not mind.
' o$ B1 t+ d& \; E/ V
, K% U* E9 v5 d9 F  I7 ?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！！！