AC pass through capacitor I am confused how AC passes through a capacitor? Can any one explain or provide any video how AC passes through a capacitor?  
 A: It doesn't. 
For DC, the current flows in one direction. Charges will flow to the capacitor plate.


*

*In the very instant where the capacitor is connected to the battery, the current flows as if there was no capacitor (a short-circuit). 

*Only after a short while will a bunch of charges have been accumulated at the plate, starting to repel the incoming charges, lowering the current. 

*after more time the current will practically stop, and the capacitor acts like an open-circuit (a "hole"). 


For AC, the current alternates. Changes direction all the time. 


*

*The charges that are accumulated at a capacitor plate are suddenly flowing away from the plate again.

*While this change of direction happens rapidly, there is never enough charge on one plate long enough to stop the current. Every time the current changes direction, in that instant it again moves as if there was a short-circuit (no "hole"). 


So for AC, it seems that current is always flowing regardless of the capacitor. Changing direction constantly, yes, but always flowing (except for the instantaneous moment of changing from forwards-to-backwards speed, where the flow of naturally momentarily is zero). This may look like current flowing through the capacitor. I believe this is called conduction current. Just keep in mind that it really doesn't - no charges jump across the capacitor gap. The effect just looks that way when looked at generally and not in detail. 
