How Does a Capacitor Work?
Do you often wonder “how does a capacitor work”? At least I asked myself that many times when I was a beginner. I really dislike the “physics explanation”. It states something like “a capacitor works by storing energy electrostatically in an electric field”. I think sentence like that didn’t make me any wiser. I like to answer this question by saying that a capacitor works like a tiny rechargeable battery with very low capacity. The time it takes to discharge a capacitor is usually only a split second. And so is the time to recharge it.
A capacitor is made up of two metallic plates. When you apply a voltage over the two plates, an electric field is created. Positive charge will collect on one plate and negative charge on the other. And this is what the physicists mean when they say that “a capacitor works by storing energy electrostatically in an electric field”.
You can combine capacitors and resistors to form filters that target specific frequencies. For example in an audio system you can target the high frequencies to remove them. This is called a low-pass filter.