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 G4 `/ Y9 g- D3 X0 `7 _5 {2 q' uif f=0 Xc is infinite, so capacitor block DC.
for 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
; n) J, Q/ A' Q# w) b为什么电容器阻断DC 而通AC?

& F- p8 Y. Y4 e6 V( A6 i( B! N; j2 u
" n6 B% {$ \+ z' t2 M6 A+ L  dI would like to ask a question, just for curiosity, if you do not mind.
* ~2 D8 `( ?2 k: b( Y* |
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！！！