# Capacitor-Types of Capacitor and Capacitance: What is a Capacitor? (For CBSE, ICSE, IAS, NET, NRA 2022)

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# Title: Capacitor - Types of Capacitor and Capacitance

## What is a Capacitor?

- The capacitor is a device in which electrical energy can be stored.
- It is an arrangement of two-conductor generally carrying charges of equal magnitudes and opposite sign and separated by an insulating medium.
- It is a passive electronic component with two terminals.
- The effect of a capacitor is known as capacitance.
- Capacitor vary in shape and size, they have many important applications in electronics.

## Use of Capacitors

**Capacitors have many uses in electronic and electrical systems**:

- Storing electric potential energy
- Filtering out unwanted frequency signals
- Delaying voltage changes when coupled with resistors.
- One of the conductors has a positive charge + Q and it is at potential + V. whereas the other has an equal negative charge, -Q and is at potential – V.

They are so ubiquitous that it is rare that an electrical product does not include at least one for some purpose.

## Charge on Capacitor

Total charge/the net charge on the capacitor is .

## Image of Capacitor

## Capacitance

- The charge on the capacitor (Q) is directly proportional to the potential difference (V) between the plates

- The constant of proportionality (C) is termed as the capacitance of the capacitor.
**Unit of Capacitance**: Farad (F)**Dimensional Formula**:

## Factors Affecting the Capacitance

- Shape and size of the conductor
- Medium between them
- Presence of other conductors near it.

## Types of Capacitor

### Parallel Plate Capacitor

- The parallel plate capacitor is the simplest form of capacitor.
- It can be constructed using two metal or metallized foil plates at a distance parallel to each other, with its capacitance value in Farads, being fixed by the surface area of the conductive plates and the distance of separation between them.

### Spherical Capacitor

- A spherical capacitor consists of a hollow or a solid spherical conductor surrounded by another concentric hollow spherical conductor.
- The capacitance of a spherical capacitor is derived as: By Gauss law charge enclosed by gaussian sphere of radius r be.

### Cylindrical Capacitor

- The capacitor is used to store large amounts of electric current in a small space.
- It is often used to store the electric charge.
- The Cylindrical capacitor is a type of capacitor that possess the shape of a cylinder having an inner radius as a and outer radius as b.