Capacitor and Capacitance

Electric current, conductance, and resistance are all concepts that we are familiar with. Capacitance, on the other hand, is a vital element of grasping the notion of electricity. You may have heard that power cannot be stored. Capacitors, on the other hand, may store electric charge. We’ll dig deeper into the notion of capacitors and capacitance in this chapter. First, let’s look at the capacitor.

Definition of capacitor –>

The capacitor, like a miniature rechargeable battery, is an electric component that can store energy in the form of electrical charges, resulting in a potential difference, which is a static voltage. A capacitor’s most basic design is two parallel conductors (metallic plate) separated by a dielectric substance. The capacitor plate is charged up when a voltage source is connected across it. Positively charged will be the metallic plate attached to the positive terminal, while negatively charged will be the plate attached to the negative terminal.

What is capacitance of a capacitor–>

A potential difference across the capacitor is caused by the accumulation of charges in the wires. The capacitor’s charge holding capacity is the quantity of charge it can hold. Capacitance is the term for this charge-holding capacity. The voltage created across the capacitor is directly proportional to the accumulated charge in the capacitor

Q  ∝ V

Then

Q = CV

C = Q / V

C is the proportionality constant, often known as the capacitance of a capacitor. The Farad(F) unit of capacitance is 1 coulomb per volt.

Calculation method of energy of capacitor

The energy is measured in joules and is equal to half of the capacitance multiplied by the voltage squared.

E=C × v² / 2

When we have a capacitor then in our mind there are the question that how to add this capacitor and how to calculate the total capacitance of the capacitor, so there are two methods to add the capacitor which are given below-

In the parallel form

The total capacitance of the capacitors in series (C₁, C₂, C₃, etc.) is:

C_total=C₁+C₂+C₃………………

In the series form

The total capacitance of the capacitors in series (C₁,C₂,C₃….,etc.) is:

1 / C_total = 1 / C₁   +1 / C₂   +1 / C₃+………..

Affecting factors for capacitor

• Surface Area: The capacitance value is affected by the surface area of the two plates. The capacitance increases as the surface area increases.
• The capacitance value is affected by the distance between the plates. The capacitance increases as the distance decreases.
• The “dielectric medium” is the type of substance that separates the two plates. The higher the permittivity of the dielectric, the higher the capacitance value.

What are the uses of capacitors?

• Both electrical and electronic uses are possible with capacitors. Filters, energy storage systems, engine starters, signal processing devices, and other applications employ them.
• Capacitors store energy that can be used by the gadget in the event of a power loss or when it requires more power.
• Capacitors are used to prevent DC current after they have been fully charged while allowing AC current to flow through the circuit.
• Capacitors are employed as sensors for a variety of purposes, including humidity measurement, fuel level measurement, mechanical strain measurement, and so on.
• In a time-dependent circuit, capacitors can be employed. Any LED or loudspeaker system might be connected to this, and any flashing light or regular beeping is likely to utilize a timing capacitor.

Conclusion

A capacitor is a two-terminal electrical component that may store energy in the form of an electric charge. It is made up of two electrical wires separated by a certain distance. The space between the conductors can be filled with vacuum or a dielectric, which is an insulating substance. Capacitance refers to the capacitor’s ability to store charges.