Capacitors store energy in the form of electrical charges.

A capacitor consists of two metal plates separated by a gap filled by vacuum or an insulating material called a dielectric. The gap can be small or large, depending on the application.

When a capacitor is charged, it stores an electric charge on the inner surface of the first plate and an opposite charge on the outer surface of the second plate. The charge between the two plates creates an electric field that repels new electronics from the first plate and attracts those already on the second plate.

Capacitors are used in a wide variety of applications, from the power supply to analog stereo equipment. They filter hum and noise caused by fluctuating current in circuits, smoothing them out and helping to improve overall circuit performance.

They are also used in power distribution to counteract the inductive loading from devices like motors and transmission lines. They are installed as individual loads or in larger groups of capacitors.

How to Select Capacitors

To correctly select a capacitor, you must know how it will work in your application and the type of environment that it will be used in. For example, if you're working with automotive power supplies, you'll need to find a capacitor that can withstand the high temperatures and humidity of under-the-hood conditions.

In addition to this, you'll need to consider what kind of voltage and frequency it will be exposed to. You may also need to determine how long it will be in operation.