Working principle of film capacitor in AC circuit(II)

We all know that any substance is relatively insulated. When the voltage at both ends of the matter increases to a certain extent, the material can be conductive, which we call the breakdown voltage. Capacitors are no exception. Capacitors are not insulators after breakdown. But in secondary school, such voltage is not seen in the circuit, so it works under breakdown voltage and can be regarded as insulator.

But in AC circuits, the direction of the current varies with time. The process of charging and discharging the film capacitor is time, and at this time, the electric field is formed between the plates, and the electric field is also a function of time. In fact, the current is passed through the formation of the field between the film capacitors. After reading the above, do you understand the principle of film capacitors in AC circuits?