Working principle of capacitor(I)

     In a sense, capacitors are a bit like batteries. Although they work differently, they both store electricity. If you have read about how the battery works, you should know that the battery has two electrodes. In the battery, the chemical reaction causes one electrode to produce electrons and the other electrode to absorb electrons.

     A capacitor is much simpler, and it can't produce electrons-it just stores electrons. In this article, you will learn about capacitors and their applications in electronics. 

    Basic knowledge of capacitors

    Like batteries, capacitors have two electrodes. Inside the capacitor, the two electrodes are respectively connected to two metal plates separated by dielectric. The dielectric can be air, paper, plastic or any other substance that does not conduct electricity and prevents the two metal poles from touching each other. With two pieces of aluminum foil and a piece of paper, you can easily make a capacitor. Although your capacitors are not ideal in terms of storage capacity, they do work.

    Capacitors in electronic circuits are shown in the figure

    Let's take a look at what happens when connecting capacitors to batteries:

    The metal plate connected to the negative electrode of the battery on the capacitor will absorb the electrons produced by the battery.

    The metal plate attached to the positive electrode of the battery on the capacitor will release electrons to the battery.

     After charging, the capacitor has the same voltage as the battery (if the battery voltage is 1.5 volts, the capacitor voltage is also 1.5 volts). Small capacitors have a low capacity, but large capacitors can hold large amounts of charges. For example, a soda can be the size of a capacitor that can hold enough charge to light a flashlight bulb for a few minutes. When you see lightning in the sky, you see a huge capacitor, one of which is the black cloud of the sky and the other is the earth, and lightning is the charge releasing phenomenon between the dark cloud and the earth. Obviously, such a large capacitor can hold a lot of charge!