Courses
Courses for Kids
Free study material
Offline Centres
More
Store Icon
Store

Difference Between Inductor and Capacitor for JEE Main 2024

ffImage

What is Inductor and Capacitor: Introduction

To explain capacitors and inductors: A capacitor is a passive electronic component that stores and releases electrical energy in the form of an electric field. It consists of two conductive plates separated by a dielectric material. Capacitors are widely used in applications such as energy storage, filtering, and timing circuits.


On the other hand, an inductor is a passive component that stores and releases electrical energy in the form of a magnetic field. It consists of a coil of wire that produces a magnetic field when an electric current flows through it. Inductors are utilized in applications such as filtering, energy storage, and electromagnetic device control. Read further for more detail.

What is Capacitor?

A capacitor is a passive electronic component that stores and releases electrical energy in the form of an electric field. It consists of two conductive plates, known as electrodes, separated by a dielectric material. When a voltage is applied across the plates, an electric field is established, and the capacitor stores electrical charge. Capacitors have the ability to store energy temporarily and discharge it rapidly when needed. They are commonly used in electronic circuits for various purposes, such as energy storage, smoothing voltage fluctuations, filtering signals, blocking direct current while allowing alternating current to pass, and serving as timing elements in oscillators and timing circuits. The properties of capacitors are: 


  • Capacitance: Capacitance is the measure of a capacitor's ability to store electrical charge. It is represented by the unit Farad (F) and determines the amount of charge a capacitor can store for a given voltage.

  • Dielectric Material: The dielectric material between the capacitor's plates affects its performance. Different dielectric materials have varying permittivity, which influences the capacitance and the ability to withstand voltage.

  • Voltage Rating: Capacitors have a voltage rating that specifies the maximum voltage they can safely handle without risk of damage. Exceeding this rating may lead to capacitor failure.

  • Time Constant: The time constant of a capacitor determines the rate at which it charges and discharges. It is the product of the capacitance and the resistance in the circuit connected to the capacitor.

  • Polarized vs. Non-polarized: Some capacitors, like electrolytic capacitors, are polarized and have a positive and negative terminal. Others, like ceramic capacitors, are non-polarized and can be connected in either direction.

  • Frequency Response: Capacitors have an impedance that varies with the frequency of the applied signal. They can act as low-pass, high-pass, or band-pass filters depending on the frequency range.


What is Inductor?

An inductor is a passive electronic component that stores and releases electrical energy in the form of a magnetic field. It consists of a coil of wire wound around a core material. When an electric current flows through the coil, it generates a magnetic field. The inductor stores energy in this magnetic field. Inductors resist changes in current flow, causing them to exhibit characteristics such as inductance, which is measured in Henry (H). Inductors are commonly used in electronic circuits for various purposes, including energy storage, filtering out high-frequency signals, generating magnetic fields, and regulating current flow in applications such as transformers, motors, and oscillators. The properties of inductors are: 


  • Inductance: Inductance is the property of an inductor that determines its ability to store magnetic energy. It is measured in Henry (H) and represents the ratio of magnetic flux to the current flowing through the inductor.

  • Magnetic Field: When a current flows through the inductor, it generates a magnetic field around the coil. The strength of the magnetic field is directly proportional to the current.

  • Self-Inductance: Self-inductance refers to the inductor's ability to generate a magnetic field in response to changes in the current flowing through it. It resists changes in current and stores energy in the magnetic field.

  • Inductive Reactance: Inductive reactance is the opposition offered by an inductor to the flow of alternating current. It is proportional to the frequency of the AC signal and the inductance of the coil.

  • Time Constant: The time constant of an inductor determines the rate at which the current flowing through it changes in response to a voltage or current input. It is defined by the ratio of inductance to resistance in the circuit.

  • Saturation: Inductors have a saturation point, beyond which the increase in current does not result in a proportional increase in magnetic field strength. Saturation can lead to changes in the inductor's characteristics and performance.


Differentiate Between Inductor and Capacitor 

S.No

Category 

Capacitor 

Inductor

1.

Function

Stores electrical energy in an electric field

Stores electrical energy in a magnetic field

2.

Energy Storage

Stores energy in the form of an electric field between plates

Stores energy in the form of a magnetic field around a coil

3.

Unit of Measurement

Farad (F)

Henry (H)

4.

Reactance

Capacitive reactance decreases with increasing frequency

Inductive reactance increases with increasing frequency

5. 

Response to DC

Blocks direct current (DC) flow

Allows DC to flow freely

6. 

Response to AC

Allows alternating current (AC) flow, impedance depends on frequency

Impedes AC flow, impedance depends on frequency


This table provides a concise overview of the main differences between capacitors and inductors in terms of their function, energy storage mechanism, unit of measurement, reactance, and response to DC and AC. A capacitor and an inductor are connected in two different configurations in electronic circuits. 


Summary 

Capacitors and inductors are two fundamental components in electrical and electronic circuits. A capacitor stores and releases electrical energy, while an inductor stores and releases magnetic energy. A capacitor stores energy in an electric field between its plates, while an inductor stores energy in a magnetic field around its coil. Capacitors and inductors play crucial roles in various electronic systems, contributing to energy storage, signal processing, and circuit behavior.

FAQs on Difference Between Inductor and Capacitor for JEE Main 2024

1. What is the role of a capacitor in an electronic circuit?

The role of a capacitor in an electronic circuit is to store and release electrical energy. It can store charge and then release it rapidly when needed, smoothing out voltage fluctuations, filtering signals, blocking direct current (DC), and allowing alternating current (AC) to pass in certain configurations.

2. How does an inductor store and release electrical energy?

An inductor stores electrical energy in the form of a magnetic field when current flows through it. When the current changes, the magnetic field collapses, inducing a voltage and releasing the stored energy back into the circuit. This process allows for energy transfer and various applications in electrical systems.

3. Can a capacitor block DC current?

No, a capacitor cannot block direct current (DC) flow. Capacitors are passive components that allow the flow of both AC and DC currents. When a DC voltage is applied to a capacitor, it charges up and reaches a steady state, allowing the DC current to pass through. However, once the capacitor is fully charged, it behaves as an open circuit for DC, preventing any further flow. So, while a capacitor cannot block DC current, it can act as a temporary energy storage device for DC circuits.

4. How does the number of turns in an inductor affect its inductance?

The number of turns in an inductor directly affects its inductance. Increasing the number of turns in an inductor increases its inductance while decreasing the number of turns reduces the inductance. This relationship is linear, meaning that doubling the number of turns will double the inductance, and halving the number of turns will halve the inductance. The number of turns determines the amount of magnetic flux produced by the current flowing through the inductor, and thus, it influences the inductance value of the component.

5. Can a capacitor store energy indefinitely?

No, a capacitor cannot store energy indefinitely. Capacitors have the ability to store and release electrical energy, but they do experience energy losses over time. These losses occur due to factors such as internal resistance, leakage current, and dielectric losses. These losses cause the stored energy to gradually dissipate, and eventually, the capacitor will discharge completely. While capacitors can store energy for a certain period, they are not capable of storing energy indefinitely without external energy sources to maintain their charge.