Difference Between Capacitor and Inductor (With Table)

Electrical devices are getting advanced day by day with technological advancements. Electrical devices use hundreds of tiny electrical units fitted into it.

Each of these units has a specific purpose to serve, each work on different principles, each having their advantages and disadvantages. These small units are put together to perform in a pre-defined way and produce results accordingly.

The two important electrical components used in various devices are the capacitor and the inductor. The capacitor and the inductor are of great importance. They are designed to serve specific purposes.

Capacitor vs Inductor

The main difference between Capacitors and Inductors is that a capacitor resists any alteration in the voltage and stores the energy in an electrical field whereas an inductor resists the change of current and stores the energy in the form of a magnetic field.

Both the capacitors and the inductors are electrical components that are used to resist changes in the electrical circuits. A capacitor is an electrical unit made by connecting parallel conducting plates separated by an insulator and an inductor is made by an insulated wire molded into a coil on a central core.


 

Comparison Table Between Capacitor and Inductor

Parameter of Comparison

Capacitor

Inductor

Resistance to

A capacitor resists the change in voltage.

An inductor resists the change in current.

Field of storage

A capacitor stores energy in an electrical field.

An inductor stores energy in a magnetic field.

Conduction of current

A capacitor does not conduct a current.

An inductor conducts current.

Preferred frequencies

A capacitor works best on high frequencies.

An inductor works best at low frequencies.

Applications

Capacitors are mostly used in high voltage power supplies, in situations of large capacitance, etc.

Inductors are used in situations where important frequencies are allowed and there is a presence of resonance, etc.

 

What is Capacitor?

A two-terminal device, invented by Ewald Georg Von Kleist, that resists any change in the voltage and stores electrical energy in an electrical field is termed as a capacitor. The effect produced by a capacitor is termed as capacitance and is measured in Farads denoted by F.

A capacitor is made of two or more plates placed parallel at a small gap between the conductive plates. These plates are separated from one another either by an insulating material or by air. The insulating layer between the two plates is termed as a Dielectric.

A capacitor cannot conduct current due to the presence of the insulating layer. It behaves as an insulator for DC and behaves as a short circuit for AC. A capacitor shows its efficiency at high frequencies.

The commonly used type of capacitors is- Ceramic capacitors, Tantalum capacitors and Electrolytic capacitors.

Capacitors are of use in high voltage supplies, in energy storage, used to maintain power when batteries are under charging, in time-dependent circuits, in converting AC to DC, in tuning circuits, in flash circuits of cameras, used as sensors, etc.

 

What is Inductor?

A two-terminal electrical component that resists any change in the current and stores energy in a magnetic field is known as an Inductor. The effect produced by an inductor is termed as inductance and is measured in Henries.

An inductor may sometimes also refered to as a choke or reactor. It is made by wounding an insulated wire around a core material, designed in such a way that when the current flows it produces a magnetic field in itself or in the core.

An inductor conducts a current through it. It conducts AC but behaves as a short circuit when DC is applied. An inductor works best on the low frequencies and when important frequencies are applied in the presence of resonance.

There are various types of inductors such as a Coupled inductor, Multilayer inductor, Ceramic core inductor and Moulded inductor. When two inductors are joined together, they behave as a transformer.

They are used to filter current in analog signals, to prevent radio frequency interference, as energy storage units in switched power supplies, in electrical transmission systems, etc.


Main Differences Between Capacitor and Inductor

  1. A capacitor is a device that resists any change in voltage whereas an inductor is a device that resists any change in the current.
  2. A capacitor stores the energy in the form of an electrical field while an inductor stores the energy in the form of a magnetic field.
  3. A capacitor does not conduct a current while an inductor conducts current.
  4. A capacitor behaves as a short circuit when an alternating current is applied while an inductor behaves as a short circuit when direct current is applied.
  5. A capacitor works with full efficiency when high frequencies are allowed whereas an inductor works with full efficiency at low frequencies.
  6. The capacitance of a capacitor is measured in Farads and the inductance is measured in Henries.
  7. A capacitor is used in high voltage power supplies with large capacitance and an inductor is used when important specified frequencies are applied in the presence of resonance.

 

Conclusion

Inductors and capacitors are two different electrical components. They have different work processes and different functions. Both are of great importance in electrical devices. They have many advantages.

But, when a capacitor and an inductor are used together in an electrical circuit, the resistance in the circuit becomes zero. When the current passes through the circuit, the current reaches up to infinity, therefore, changing the electrical potential of the inductor.

When the potential of the inductor is greater than that of a capacitor then the current flow in the reverse direction thereby charging the capacitor. This process repeats infinitely due to the absence of the resistance.

When the capacitor and the inductor are used together, they work as a filter for current. There are many other uses of the two together. Together they are used to create a filter for analog circuits and also used in LC circuits where the circuit works as a resonator.

These circuits are used in amplifiers, oscillators, mixers, surveillance systems, etc. These are used to generate signals at specific frequencies. Therefore, using capacitors and inductors separately or placing them together in a circuit, both play an important role


References

  1. https://ieeexplore.ieee.org/abstract/document/4432307/
  2. https://www.worldscientific.com/doi/abs/10.1142/S0218126618501700