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How Does A Capacitor Work

time 2022-11-21

Publisher: hqt


How Does A Capacitor Work

Capacitors are used in almost every electronic device. From cell phones to computers, from radios to televisions and from headphones to flashlights. They are indispensable for ensuring the smooth flow of electricity and storing it safely for later use. In this blog, we will discuss about what is a capacitor, how does a capacitor work and different types of capacitors. After reading this blog, you will have a clear understanding of this useful but little-known device.

What is a Capacitor?

A capacitor is a device that stores energy in an electrostatic field. It is a pair of conducting materials separated by an insulating material. Electrostatic field is created by charging one end of the capacitors with a direct current (DC) voltage. This charging is done by a source of direct current electricity or a battery. The charged capacitor holds a specific amount of energy proportional to the charge applied. This energy can be later used to power an electronic device. A capacitor works on a basic principle of electrostatic induction. Electrostatic induction is a phenomenon in which positive charges in an object cause a partial negative charge to be induced in surrounding materials. This process is the same for capacitors and batteries. When a capacitor is charged from a battery, the electrons in the battery flow through the external circuit, through the wires and get charged on the inside of the capacitor. As soon as these electrons stop flowing, the outside circuit is broken and the capacitor loses its charge.

How Does a Capacitor Work?

Electrostatic field between two charged plates of the capacitor is used to store energy by the electric charges. When a button or a switch connected to the capacitor is pressed, electrons flow from the negative plate of the capacitor to the positive one. Like a battery, capacitor is also an electrical device and needs energy in the form of electricity to work. In this process, electrons enter into the positive plate of capacitor and leave through the negative one. Now, the electrostatic field collapses and the charge stored in it loses energy. The capacitor now stops storing any amount of energy and the button or switch is no longer pressed. In this way, a capacitor converts stored energy from electricity into mechanical energy.

Types of Capacitors

There are many types of capacitors, depending on the material used for their construction. Paper or Mylar capacitors are the most popular and widely used in electronic devices. They find use in radios, radioscrapers, flashlights, cameras and other small electronic devices that do not require a lot of energy storage. They work on the principle of electrostatic induction and allow for a small amount of current to flow through them. Electrolytic capacitors store more energy than paper capacitors and are commonly used in computers, laptops, power banks and other large electronic devices. These capacitors utilize the electrolytic process of generating electricity. These are basically two types of capacitors: – Disc capacitors – These are thin, circular, circular discs made of paper, plastic or Mylar. – Stack capacitors – These are similar to disc capacitors but are stacked in a parallel circuit. Both of these types of capacitors work on the same principle of electrostatic induction. However, stack capacitors have the advantage of being able to store more energy than the disc capacitors.

Benefits of Using Capacitors

– Storing Energy – When power comes from an external source, such as a battery, solar panel or a socket, energy flows through the external circuit and goes back to the source. Capacitors store this energy and do not let it go back to the source. When a button is pressed, capacitor discharges and the energy stored in it is now available to run the device. – Improving Efficiency – When we use a switch to control a device, it requires a certain amount of energy to work. This energy is often wasted because a switch does not use it efficiently. The capacitor stores this energy in a more efficient manner and gives it to the electronics when needed. This increases the efficiency of the whole system. – Long Lasting – Since a capacitor is a steady DC source of energy, it does not get disturbed and stops functioning when the external voltage decreases. It stores the energy for a longer time and is used in devices like cordless phones, power banks, clocks and other appliances that have a continuous power requirement.

How to Install a Capacitor in Circuit?

A capacitor is nothing but a pair of metal plates connected by a conducting wire. An insulating material is placed between the two metal plates. Now, a wire connects to the circuit of the electronic device and the other end is connected to the capacitor. When button or a switch connected to the capacitor is pressed, the capacitor discharges and the energy stored in it charges the circuit. Now, the capacitor cannot create its own current and needs a source of direct current to charge it. This direct current can be obtained from external batteries, solar panels or any other source. The circuit of the electronic device is now powered by the capacitor.

Useful Tips for Working of Capacitors

– A capacitor does not have a switch or a button similar to a battery. It is a passive device that does not consume any energy. It can be connected to any circuit and does not require a switch or a button. However, it may not work if the voltage applied to the circuit is less than the voltage stored in the capacitor. – Always keep the exposed ends of a capacitor clean and dry. It is very important to maintain the insulating material between the plates of a capacitor. If it is damaged or if it is not kept clean, the capacitor will not work properly. – A capacitor can only work with a source of direct current of same polarity. If a capacitor is connected to a circuit that requires a positive polarity of current, it will not work. – It is better to store energy in a capacitor during peak hours of sun’s energy. Considering the fact that most of us use electricity during night, it is recommended to store energy in a capacitor during daytime for easyiee


Question: What is the best capacitor to buy? Answer: The best capacitor to buy depends on the application. Paper, electrolytic and oil-filled capacitors all function on the same principle of electrostatic storage and can be used for almost any application. However, disc capacitors are cheaper and can be used in low-voltage applications like low-powered flashlights or radios.

Question: How long will a capacitor last? Answer: This depends on the quality of the capacitor and the application. However, a good quality capacitor will provide electricity for at least ten years with no damage to the device connected to it.

Question: How can I tell if a capacitor has run out of power? Answer: You can easily tell if a capacitor has run out of power. First, disconnect the circuit from which it is charging. Then, short-circuit the capacitor with a short circuit that is connected to a live circuit. Now, the capacitor will work and you will be able to see the spark in between the two short-circuit wires. These are some of the basic facts about capacitors. They are a very useful device that stores energy and can be used in almost every electronic device. Now that you know more about capacitors, you can use them to their fullest potential in your daily life.