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)
0 K7 J1 X0 ~/ M* L! L6 n5 yif 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
) ~* i/ ~6 }$ a5 M4 [/ p( `! P) J. v为什么电容器阻断DC 而通AC?

2 M7 f  J6 b5 G( F7 W+ [7 Y& i
I would like to ask a question, just for curiosity, if you do not mind.
: z3 }7 c6 Y1 R9 _
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！！！