dielectric is used in a capacitor to isolate two capacitor metal plates. in a dielectric material if you apply a voltage through it then no current will pass through it but the dielectric material will be polarized on two sides of the material positive and a negative charge will appear. the number of positive and negative charges in the capacitor plate depends on the voltage applied to the dielectric material.
All dielectric materials are insulators but good dielectrics can be easily polarized. the electric charge is stored in the dielectric field. changes in the electric field within these two metal plates produce a magnetic field. the current induced in two capacitor plates is called the displacement current. this displacement current is induced because of changes in the electric field in the capacitor. The dielectric is present between two capacitor plates to hold the flow of conduction current in it.
This conduction current fills the capacitor plate if it is in the same direction, but if it is two-way in nature then after being charged simultaneously it will be released at the same time it cannot hold the electric charge .. the capacitor is used as the energy stored element.
the polarizing behavior of itself from the dielectric material while the voltage applied to it helps to store the electric charge inside it. because the capacitor is supplied higher than the rated voltage, the damage to the dielectric material occurs in the capacitor which makes the capacitor damaged.
first, the capacitor becomes a capacitor because of the dielectric between the two conductor plates.
after the dc power supply is applied, the charge flows in the circuit only to reach the dielectric and is blocked by it. these costs are collected at the conductor plate until the plate reaches its maximum capacity. at this point, the charge flow stops.
Initially, you can measure the current on the circuit that stops when the plate reaches saturation. the stored charge will be such that for every positive charge on one plate, a negative charge will appear on the other side. at this time, if you connect a voltmeter across the dielectric you can see the presence of voltage. This capacitor with a filled plate is similar to a battery that can be recharged with a short usage time.
This does not apply when the AC supply is applied. because it changes the direction continuously, the capacitor will be charged during the ac signal increase and released by the fall of the signal. You can see here that current flows are similar to those in normal cables. hence, for ac signal capacitors acting like short.
so that with a dielectric between two conductor plates, the current can be blocked and without affecting the ac current in the circuit. it can also be used as a small battery at the time.
if there is no dielectric on the capacitor, it becomes like a simple conductor which passes electricity only that is an experiment where the capacitor maker places the dielectric b / w of the conductor and then he considers that storing the charge is not a current You can also make capacitors at home and see what will happen when you put dielectric and remove the dielectric from the two conductive plates